Hello people.

I know, I'm becoming an ass about this. But I'm really tired of seeing linear-encoded renders.

None of us has a display device encoded in linear color space. We all have monitors and printers that show images correctly if they are in sRGB color space.

Linear color space is similar to sRGB color space. It is not the same.

Inches are similar to centimeters, too, but you can't just replace one with another.

In sRGB color space, the value .5 is not 50% as bright as 1. It is only 21.7 % as bright. Please stop posting renders for devices nobody owns. Or, when you post such images, apologize to the viewer for making them look at something you could easily correct, but you refuse to.

Thank you.

Renderosity forum reply notifications are wonky. If I read a follow-up in a thread, but I don't myself reply, then notifications no longer happen AT ALL on that thread. So if I seem to be ignoring a question, that's why. (Updated September 23, 2019)

o.k., will do - thx fr the reminder. does the problem of users having their displays set wrongly enter into this? (see att. img)

Dear bagginsbill,
I save my renders as png's and post them as jpeg's, how does that differ form sRGB encoding? I do, however, after postwork now save my work using Photoshop's 'Save for web' command so as not to exceed Renderosity's 510 kilobyte limit, is that what you're referring to?
Yours truly,
David P. Hoadley

STOP PALESTINIAN CHILD ABUSE!!!! ISLAMIC HATRED OF JEWS

Just upgraded to Poser Pro! (off-topic: wheee, it's my birthday gift! Happy birthday to me!)

So if I use textures and shaders not already gamma-corrected on their own, I just need to leave the "default gamma correction" to 2.2 and I am OK, right?

Otherwise I just say "do not use gamma correction for this specific texture" if something is already gamma-corrected... kick me if I am wrong.

Giorgio

giorgio_2004 here, ksabers on XBox Live, PSN and everywhere else.

i am happy bagginsbill make this thread.

i know what the problem is. 70-80% of Poser users are just opening a document and using almost everytime the default settings. i understand this when you use poser for 1 month. but after 6 months or 12 months you should know enough that you need to gamma correct your renders.
if you have poser pro you have this in the render settings. if you have poser 7 then you should use bagginsbills skin shader that has GC inside. plus he already explained how to make a default GC shader. from there on you can do whatever you want to do.

here is explained ho to do GC shaders
http://www.renderosity.com/mod/forumpro/showthread.php?thread_id=2738989&page=1

here you have teh GC skin shader
http://www.renderosity.com/mod/forumpro/showthread.php?thread_id=2737823

so pleeeeeeeeease no mroe orange glow on teh skin. ohhhh and stop buying light sets for christ sake. you have lights in your software already. you choose what color and what shadows you will have. stop using 7 lights or more in a render. this is insane. with GC shaders and a good IBL you are able to fake some GI.

@ DPH, You mention in your "Who do I have to bribe..." thread that you use a set of 4 lights on average. What intensity are those lights set to?
Have a look at this image:www.renderosity.com/mod/gallery/index.php

There is no post work done on this image. I save as .TIF out of Poser and use GIMP to save as sized JPG for uploading. There are 3 lights in this scene, 1 IBL @ 25% w/AO, 1 point @10% and another point @40%.

With Gamma Correction fewer lights at lower intensity are needed to produce a well lite scene. And changing the lights does what you expect it to, the scene can be made to look more natural more easily. The less time I spend trying to correct (after the fact) an image the more time I can spend on the layout/creation of the image. By the way that image would not be half as realistic without all the tips and techniques bagginsbill has put out on the forums over the last couple of years. Thanks BB.

Quote - o.k., will do - thx fr the reminder. does the problem of users having their displays set wrongly enter into this?
(see att. img)

FYI: I got a pantone huey to calibrate my Mac Cinema displays. It appears that Macs are set to 1.8 currently, not 2.2.

Gary

"Those who lose themselves in a passion lose less than those who lose their passion"

Bagginsbill,

I was hoping you could link me to a thread where you may have posted anything in the format of "The Complete Idiot's Guide to Gamma Correction" which might include a screen shot of the node chains.......showing the primary and secondary diffuse parameters, etc.

I thought I saw something...... but I'll be damned I cannot search and find it again......
Thanks

______________________

"When you have to shoot ...

SHOOT.

Don't talk "

- Tuco

Santicor's Gallery:

http://www.renderosity.com/homepage.php?page=3&userid=580115

Attached Link: http://www.renderosity.com/mod/forumpro/showthread.php?thread_id=2738989&page=1

to Santicor: the above thread is what you need, I believe. It's the first of the two links posted by ice-boy above, except they weren't hyperlinked. Here it is again, nice 'n' easy!

to Holler: I love that image. It is simple (in a good sense), elegant work like this that re-inspires me to go back to the basics with Poser when all my renders are coming out wrong. Thanks, both to you and (indirectly) to bb!

to grichter: there was a news item a little while back to the effect that Apple are in future going to use GC 2.2 for all their displays. Whether / when this is happening I do not know, and I'm not yet sure of the consequences for current Apple display users like you'n'me.

"If I were a shadow, I know I wouldn't like to be half of what I should be."
Mr Otsuka, the old black tomcat in Kafka on the Shore (Haruki Murakami)

Attached Link: LCD Monitor Tests

re: gamma and other stuff ...

FYI - If you have an LCD monitor, you might be interested in this information.

Check your gamma ... and other stuff.

cheers,
dr geep
;=]

Remember ... "With Poser, all things are possible, and poseable!"

cheers,

dr geep ... :o]

edited 10/5/2019

that's it IsaoShi !!!

oops ...didn't notice they were here in the thread :-O

molto bene ......grazie

______________________

"When you have to shoot ...

SHOOT.

Don't talk "

- Tuco

Santicor's Gallery:

http://www.renderosity.com/homepage.php?page=3&userid=580115

*I know what the problem is. 70-80% of Poser users are just opening a document and using almost everytime the default settings. i understand this when you use poser for 1 month. but after 6 months or 12 months you should know enough that you need to gamma correct your renders.
if you have poser pro you have this in the render settings. if you have poser 7 then you should use bagginsbills skin shader that has GC inside. plus he already explained how to make a default GC shader. from there on you can do whatever you want to do.

*I'm using poser for 12 years and I never gamma-corrected my renders, and in every post I made no one told me that I had to gamma-correct it. I have poserpro but I didn't use the gamma correction, because pro messed up the bump, transparancy and displacement maps, which shouldn't be gamma corrected. Until now I had my monitor-settings on 9200K because I found the sRGB settings much too low: not only with my poser renders, but with everytihing: WIndows, internet explorer, autocad, you call it.
But perhaps the fact that I'm getting a little older (51) my eyes are degrading and as a CAD-draftsman I have not much experience with working with photoshop or paintshop. Perhaps I have too work more with that.
I changed my monitor settings to sRGB and I will see if I can get used to it. Perhaps it will improve my renders.

best regards,

Bopper.

-How can you improve things when you don't make mistakes?

I tried to do a search here for a thread started by Bagginsbill about gamma correction and gave up after looking through a few, but did find the one that **IsaoShi** did. Maybe Acadia can add the main link to the Materials sticky thread.

Are there any advantages to using gamma correction within Poser versus doing it in postwork?

The problem doing it in Poser is that it requires a render to fully see what the lights are doing and, depending on the complexity of the models in the image, that could take many minutes to hours to see. In postwork, all changes are dynamic and immediately seen. A lot more experimentation can be done in postwork in little time instead of tweaking and rendering in Poser time after time. My basic workflow is to get the lighting as good as I can in Poser and then bring it into Photoshop to punch up the colors as I did in the above image. The top image is what came right out of Poser and the bottom shows just the change from using Photoshop curves to enhance the colors I wanted to bring out.

The one thread where I saw gamma correction used in Poser, in an earlier thread, the nodes were fairly complex. If memory serves me right, those nodes had to be be applied to each texture. It wasn't a one-time solution.

My visual indexes of Poser content are at http://www.sharecg.com/pf/rgagnon

bopperthijs,

Your recent (excellent) renders are using VSS shaders, no? Did you turn off GC in those shaders? Because if you did not turn it off, then it is on, and you have been rendering with GC.

gagnonrich

That looks good to me. Doing GC in photoshop with levels and curves is fine in the right hands. You obviously have the right hands. :)

Renderosity forum reply notifications are wonky. If I read a follow-up in a thread, but I don't myself reply, then notifications no longer happen AT ALL on that thread. So if I seem to be ignoring a question, that's why. (Updated September 23, 2019)

in PS you have now gone past the point where you were able to isolate separate materials, as in the Poser render setup, so you will apply levels and curves in PS to the image as a whole .... UNLESS you want to try and lasoo select different parts of the image and repaste them all down as different layers, then you are asking for trouble because of transition from selected piece to selected piece, UNLESS you soft edge erase each contiguous edge between different pieces. It starts to get messy though. For that matter, if you want to post in PS, why not just shine differnt lights all over the image in PS with the PS render options......point is: I bet it's better control in the PS material room, although it takes longer , granted I suck at rendering in Poser up to this point but I bet it is a better result.

______________________

"When you have to shoot ...

SHOOT.

Don't talk "

- Tuco

Santicor's Gallery:

http://www.renderosity.com/homepage.php?page=3&userid=580115

Hi Baggingsbill,

I did use GC in those shaders and I was aware of that, but only on the skin shaders, I didn't use it on other materials. Perhaps that is one of the reason why my environment looks dull now and them.

-How can you improve things when you don't make mistakes?

Quote - UNLESS you want to try and lasoo select different parts of the image and repaste them all down as different layers

Or render separate elements that can be selected separately in Photoshop. I did separate renders of the diver and the creature, but not for coloring purposes. For the final image, I did a radial gradient layer and applied a blur, centering on the tunnel entrance, to simulate distance on the cave, but didn't want it to affect the main figures (I manually added a distant blur to the creature's neck).

Color corrections usually only need to be applied globally on a Poser render. It's possible to select and paint individual elements, but that's not usually necessary. I'd rather fix an isolated color issue in Poser so that all the lights and shadows act on that element appropriately. I'm all for letting Poser do the bulk of the work. Poser has its limits or sometimes takes more effort to achieve a result than can be done in other programs. Photoshop, and other image editors, excel on fixing the color on images. Image editors are less useful in lighting an image and general light arrangement for 3D graphics are best addressed in the 3D programs.

I'd imagine that most people prefer the second image over the first. All I did was add contrast with an "S" curve and similarly beefed up the red and blue channels. I don't know if that can readily be done in Poser. Even if it could, the process would be change settings, render, and repeating till the right result is achieved. In Photoshop, I alter the curve and the result is nearly instantaneous, so I can do a lot more experimentation in a shorter time than I can with Poser.

In the end, methodology doesn't matter as much as results. The quality of any image relies on the image itself and not the tools used to create it.

Methodolgy discussions are still useful because there's always something to learn from them. That's why I'll often read something from bagginsbill. He knows a whole lot more about this stuff than I do. If there's a faster way in Poser to achieve the results I got in the second image entirely within Poser, I'm all for learning it. I rather doubt, even applying gamma correction in Poser, that the results would be as good as what could be done in Photoshop. It would probably be less flat than the first image. I wouldn't want to spend a lot of time getting Poser a little better and then essentially doing as much work in Photoshop as before.

My visual indexes of Poser content are at http://www.sharecg.com/pf/rgagnon

OK, can someone translate this thread into "totally clueless"? I know gamma has something to do with display settings and can make things harder to see if you have it set wrong, but that's about all. I'd like to learn more about this.

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I use Poser 13 and win 10

*Or render separate elements that can be selected separately in Photoshop.

*A good point and a simple procedural concept that I did not consider

Thanks

______________________

"When you have to shoot ...

SHOOT.

Don't talk "

- Tuco

Santicor's Gallery:

http://www.renderosity.com/homepage.php?page=3&userid=580115

Attached Link: http://en.wikipedia.org/wiki/Gamma_correction

It's just a matter of how brightness is represented in a display device. A perfectly calibrated monitor emits a certain amount of light (in each of red, green, and blue) based on a number we put in each pixel color component.

There are two common systems for talking about these values. The fractional system, i.e. 0 to 1 in fractions of a whole. As in 1 = as bright as is possible, and 0 = no light emitted whatsoever. Levels in bewteen are numbers such as .125, .38435, .98483. The bigger the number, the brighter it is. The other common representation is integers from 0 (nothing) to 255 (maximum).

[[
Why 255? If you don't care, skip this. Most computer displays are set up using 8-bit integers for each color component. Using 8-bit binary numbers, the largest value is 2 to 8th power minus 1, which is 255.

Conversions between the two are straightforward. For example, .3 * 255 = 76.5 - rounding up the value is 77. To go the other way, divide by 255. For example, 150/255 = .588 approximately.
]]

These things have nothing to do with gamma correction - I'm just giving you an intro.

Now the question is, what does .5 mean on your computer screen. Is that half of the maximum? The answer is no. There's a lot to why, but basically just accept it. To get half as bright as the maximum, the correct fraction is not .5, but rather .73.

Prior to Poser Pro, Poser did not generate numbers like this properly representing fractions of maximum brightness adjusted for your computer display. Instead, it uses straight linear values.

For example, suppose you render something with a Poser light at 90% intensity, and the value produced in the image is .7. Suppose you then cut your light intensity in half, to 45%. What value will Poser render now? It will render .35, half of .7. That is linear intensity scaling.

But your screen doesn't work that way. The value .7 looks like about 46% of maximum brightness, not 70%. And the value .35 looks not at all like 35% of maximum brightness. It actually looks like 1% of maximum, which is to say basically invisible.

To find out what a given fraction x actually looks like, you take the fractional value and raise it to the power 2.2.

The only values that are the same in linear color space and sRGB (monitor) color space are the values 0% and 100%. (Completely off, and completely on at maximum)

All other in-between values are not the same. They must be converted in order to make sense. It is a little bit like temperature scales. Between Fahrenheit and Celsius, there is only one value that means the same thing in both. That value is -40. The temperature -40 means the same in either system. But all other temperatures are represented by different numbers. A 0 in Celsius is 32 in Fahrenheit.

To deal with this, we need the render to be pre-compensated. Meaning, if the render is trying to produce a brightness of 60%, for example, we need to find out what value to put in the image that, after the monitor darkens it, comes out to 60%. That value is called a gamma corrected value. To produce 60% brightness, you need to use .6 to the 1/2.2 power, which is actually .793.
That is for a gamma of 2.2. But some Mac computers are set up at 1.8 - so to see them right you'd need a gamma correction of only 1.8, not 2.2.

This is why many nice looking MAC images look dark on a PC, and many nice looking PC images look extra bright on a MAC. (This was a little marketing ploy by Apple - people think pictures look nicer on a MAC because they are brighter. Basically the MAC applies some gamma correction (1.4) automatically, causing most photos to look extra bright and sparkly.)

Poser Pro has finally acknowledged this in the rendering process. If you don't have Poser Pro, you have to either correct your numbers in postwork, or set up shaders to do it, or use a device in your render I call a gamma correcting lens.

I don't care what you preference is for technique, I just want to see pictures accurately shown on a computer screen. And you should, as well.

It matters, because there are a boatload of people who think lighting in Poser is difficult. It is not difficult. It is actually pretty easy, if you were to actually convert your final image to the right data representation for viewing on a computer screen. The linear format produced by Poser is mathematically correct, but not actually ready to look at on your screen.

It is unfortunate that linear format and sRGB format look sort of similar. In both, bigger numbers are brighter than smaller numbers. In both, equal amounts of red, green, and blue produce a shade of gray, but the actual brightness of that gray is different between the two systems. Our willingness to dismiss the relative ugliness of Poser renders is entirely a result of the unfortunate similarity between the two systems. Had they been more wildly different, nobody would have ever put up with the incorrect representation of brightness produced by displaying linear images on a computer screen.

PS: I corrected a bunch of spelling errors but there's probably a lot more in my post. Sorry.

Renderosity forum reply notifications are wonky. If I read a follow-up in a thread, but I don't myself reply, then notifications no longer happen AT ALL on that thread. So if I seem to be ignoring a question, that's why. (Updated September 23, 2019)

Attached Link: http://www.curtpalme.com/forum/viewtopic.php?t=6861

Here's an interesting little article talking about a home-theater gamma correction device that reveals all kinds of stuff in movies that are otherwise invisible.

This is not necessarily because of linear rendering, but sometimes it is. Sometimes even movie special effects guys forget to gamma correct.

Renderosity forum reply notifications are wonky. If I read a follow-up in a thread, but I don't myself reply, then notifications no longer happen AT ALL on that thread. So if I seem to be ignoring a question, that's why. (Updated September 23, 2019)

Attached Link: http://www.poserpro.net/King_Tut/Gamma/PoserPro_Gamma.html

See also this

The opening paragraph says it all.

Quote - Gamma Correction is probably one of the most baffling and misunderstood concepts in existence. You will find more written about it than you can possibly need or want to digest, and each author will make their own unique attempt at explaining the �ins-and-outs-and-what-have-yous� when in reality most of us don�t really care, and don�t even realize that we�re affected by it almost every time we turn on a computer. Unfortunately when it comes to creating stellar 3D graphics, the use of gamma correction becomes very necessary, even though an in depth understanding of it does not. Fortunately Poser Pro contains some straight forward options for using Gamma Correction. This document attempts to explain the necessity as it relates to Poser Pro in a practical manner while giving you a basic understanding of the process by which you can produce excellent Gamma corrected images using Poser Pro. In effect we�ve tried to simply as much as possible and keep it pertinent.

Renderosity forum reply notifications are wonky. If I read a follow-up in a thread, but I don't myself reply, then notifications no longer happen AT ALL on that thread. So if I seem to be ignoring a question, that's why. (Updated September 23, 2019)

Attached Link: http://www.poserpro.net/King_Tut/vids/Gamma/Poser_Pro_Gamma.htm

Poser Pro video.

Even if you don't have Pro, you should watch so you know what you're not doing right.

And then find a way to do it.

Renderosity forum reply notifications are wonky. If I read a follow-up in a thread, but I don't myself reply, then notifications no longer happen AT ALL on that thread. So if I seem to be ignoring a question, that's why. (Updated September 23, 2019)

Here is a little test render, in linear color space. Can you see all the balls? Can you see their shadows on the ground? Probably not.

Renderosity forum reply notifications are wonky. If I read a follow-up in a thread, but I don't myself reply, then notifications no longer happen AT ALL on that thread. So if I seem to be ignoring a question, that's why. (Updated September 23, 2019)

Here is the true scene, converted to sRGB color space via gamma correction.

Renderosity forum reply notifications are wonky. If I read a follow-up in a thread, but I don't myself reply, then notifications no longer happen AT ALL on that thread. So if I seem to be ignoring a question, that's why. (Updated September 23, 2019)

Quote - Hello people.

I know, I'm becoming an ass about this. But I'm really tired of seeing linear-encoded renders.

None of us has a display device encoded in linear color space. We all have monitors and printers that show images correctly if they are in sRGB color space.

Linear color space is similar to sRGB color space. It is not the same.

Inches are similar to centimeters, too, but you can't just replace one with another.

In sRGB color space, the value .5 is not 50% as bright as 1. It is only 21.7 % as bright. Please stop posting renders for devices nobody owns. Or, when you post such images, apologize to the viewer for making them look at something you could easily correct, but you refuse to.

Thank you.

How do you gamma correct a render?

I know about calibrating monitors, but I've never heard of calibrating/gamma correcting a poser render before.

"It is good to see ourselves as others see us. Try as we may, we are never
able to know ourselves fully as we are, especially the evil side of us.
This we can do only if we are not angry with our critics but will take in good
heart whatever they might have to say." - Ghandi

Note to people using V4... it comes with some shaders to help images that aren't gamma corrected so you are going to have to deal with those if you plan to gamma correct. Unfortunately at least some of the character sets that you can buy for her have that problem as well.

For example if you use a lens like bill, a 2.2 value in the divisor will make the whites of her eyes look red. Use 1.5 and they look gray.

WARK!

Thus Spoketh Winterclaw: a blog about a Winterclaw who speaks from time to time.

(using Poser Pro 2014 SR3, on 64 bit Win 7, poser units are inches.)

This is what happens if you don't do any prep for gamma correcting.

Also note that the eyes seem to always give me troubles. I have tried 8 raytrace bounces with just the "base" lens that has just the refract node and they still come out dark like that.

(left side is without the lens, right side is with it)

WARK!

Thus Spoketh Winterclaw: a blog about a Winterclaw who speaks from time to time.

(using Poser Pro 2014 SR3, on 64 bit Win 7, poser units are inches.)

Realmling is having the same problem - posting about it in the lens thread.

I just made a suggestion - seems there is some wierd faking of SSS based on transparency and the back part of the eye is colored solid red.

Try removing the transparency on the sclera.

Renderosity forum reply notifications are wonky. If I read a follow-up in a thread, but I don't myself reply, then notifications no longer happen AT ALL on that thread. So if I seem to be ignoring a question, that's why. (Updated September 23, 2019)

The character I'm using (Sabryn's Coryn) doesn't have any sclera transparency. Viki4 does have a transparent eye surface node though. Looks like it is covering the eyes.

Turning that off helps, but then you can't see anything underneath it.

WARK!

Thus Spoketh Winterclaw: a blog about a Winterclaw who speaks from time to time.

(using Poser Pro 2014 SR3, on 64 bit Win 7, poser units are inches.)

Quote - How do you gamma correct a render?

I know about calibrating monitors, but I've never heard of calibrating/gamma correcting a poser render before.

Isaoshi linked you above to my thread on how to build a GC shader.

Here is a link to the Artistic Lens thread, wherein I show how to do it with a prop.

http://www.renderosity.com/mod/forumpro/showthread.php?thread_id=2754029

And here is my previous GC reminder thread. Some interesting stuff to read there if you missed it.

http://www.renderosity.com/mod/forumpro/showthread.php?thread_id=2757170

Somebody in that thread asked how to do it with PSP 9. I don't know the answer. I don't know how in postwork - I don't do that. I know that Photoshop "Levels" and move the middle slider to the left is somewhat like GC, but mathematically not identical.

Renderosity forum reply notifications are wonky. If I read a follow-up in a thread, but I don't myself reply, then notifications no longer happen AT ALL on that thread. So if I seem to be ignoring a question, that's why. (Updated September 23, 2019)

Quote - *

*I'm using poser for 12 years and I never gamma-corrected my renders, and in every post I made no one told me that I had to gamma-correct it. I have poserpro but I didn't use the gamma correction, because pro messed up the bump, transparancy and displacement maps, which shouldn't be gamma corrected. Until now I had my monitor-settings on 9200K because I found the sRGB settings much too low: not only with my poser renders, but with everytihing: WIndows, internet explorer, autocad, you call it.
But perhaps the fact that I'm getting a little older (51) my eyes are degrading and as a CAD-draftsman I have not much experience with working with photoshop or paintshop. Perhaps I have too work more with that.
I changed my monitor settings to sRGB and I will see if I can get used to it. Perhaps it will improve my renders.

best regards,

Bopper.

when you open image map you have an option to change the GC for the image itself. you can writte in what ever number you want.

GC comparison- newbie style.....

I did the head only, and there is some kind of change.......I set up the nodes for GC the way Bagginsbill said to do it for Simon in this thread:
http://www.renderosity.com/mod/forumpro/showthread.php?thread_id=2738989&page=1

The ONLY difference is in the "math function 2", "Value 2" i had to turn down to about .2 or else she had a crazy intese bright glare, as if the light intensity was quadrupled or something....along with lowering this value, I decreased the intensity of the lights - I am only using 2 white spots , distributed evenly on her face and upper body. about 40-50% intensity

My obvious problem here is that even with white lights, and SOME twisted newbie form of GC......Sydney still looks like she is floating in a glass of cognac

______________________

"When you have to shoot ...

SHOOT.

Don't talk "

- Tuco

Santicor's Gallery:

http://www.renderosity.com/homepage.php?page=3&userid=580115

A rough rule of thumb, to color correct most images in postwork, is to make sure that the darkest part of the image is pure black, the lightest part of the image is pure white, and that shades of gray have no other colors mixed in. Photoshop's levels and curves have three eyedroppers that do just that. Clicking in the appropriate parts of the image with those eyedroppers often gets pretty close to the correct colors in the image. Sometimes clicking with the eyedropper will produce an undesired result, but CTRL-z usually reverts it to its previous state and cancelling will get rid of all changes done in curves or levels if things are going too bad.

What this is basically doing is establishing a dynamic range in the image. An image without a pure black or a pure white often looks dull or muddy because it lacks good contrast. If an object, that is supposed to be gray, isn't, then there is a color cast to the image. Making the gray object gray will often get rid of the color cast.

As with everything, there can be exceptions because not all images are alike. Some images don't have anything that ought to be pure black or white. Others have an intentional colorcast.

With the original image of my underwater cave scene, the darkest black is a dark gray and the lightest white a light gray. By forcing the darkest black and lightest white to pure black and white, the figures pop out of the background. Increasing the blue channel in Photoshop got rid of the yellow colorcast in the original image (yellow being the opposite of blue light).

My visual indexes of Poser content are at http://www.sharecg.com/pf/rgagnon

> Quote - GC comparison- newbie style..... > > I did the head only, and there is *some kind* of change.......I set up the nodes for GC the way Bagginsbill said to do it for Simon in this thread: > [ http://www.renderosity.com/mod/forumpro/showthread.php?thread_id=2738989&page=1](http://www.renderosity.com/mod/forumpro/showthread.php?thread_id=2738989&page=1) > > The ONLY difference is in the "math function 2", "Value 2" i had to turn down to about .2 or else she had a crazy intese bright glare, as if the light intensity was quadrupled or something....along with lowering this value, I decreased the intensity of the lights - I am only using 2 white spots , distributed evenly on her face and upper body. about 40-50% intensity > > My obvious problem here is that even with white lights, and SOME twisted newbie form of GC......Sydney still looks like she is floating in a glass of cognac

There's something you're not telling me.

If you put .2 in Value_2 of Math_Functions_2, what you did was multiply the gamma correction factor (2.2) with .2, giving us .44 which is the oppposite of gamma correction. That would be going the other way.

This is what that looks like.

Are you using Poser Pro? Did you accidentally turn on GC in Pro, thus doubling the amount of GC?

Renderosity forum reply notifications are wonky. If I read a follow-up in a thread, but I don't myself reply, then notifications no longer happen AT ALL on that thread. So if I seem to be ignoring a question, that's why. (Updated September 23, 2019)

Here is what I get with a variant of that shader.

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Here's the shader I just used.

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This time rendered with shadows.

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I'm using only an IBL and one infinite. The infinite light is only at 60%.

The IBL light intensity you should use depends on what is in the image so I can't tell you what to use.

But here is a render with IBL only, no infinite light. You should see something like this with your IBL only render as well. If you see brighter than this, you have too much IBL. Most people do.

Remember, all the extra light you used to use was a hack in response to the darkness you saw without GC. Use less light.

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This is the IBL only render without GC turned on in the shader. I doubt you started with your light this low. Nobody is used to using such a low light.

If your non-GC render looks brighter than this, you're starting with too much light.

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This is with my infinite light at 100%. While that is very bright, it doesn't look messed up. It just looks like a very bright light.

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Here is my infinite at 200%.

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Guess what. GC also fixes the cases where you have a lot of light.

Here is the same 200% infinite, but the skin does NOT have the GC turned on. Looks crazy, eh? That doesn't look at all like a human standing in front of a serious light. It just looks wierd.

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Of course, the shader above is just a basic gamma correcting shader. It's not doing anything specific for skin.

If you put a proper skin shader on, like this, the realism will go up.

This is the skin shader I'm building for the Antonia character. It is designed to be used without any texture (color) map at all. But here plugged in Sydney's texture.

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Here is the VSS Preview Release 3 skin shader. This was designed to work with color maps.

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*"There's something you're not telling me...... "

*LOL ! love the way you put that ......yeah I am kinda not sure If I had the shader exactly perfect

ANYWAY: I will get this right tonight when I get home, can't check my nodes right now I'm at work. Try to install MSN messenger here and the police show up, let alone something like Poser

Thanks this is awesome information

______________________

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Don't talk "

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@BagginsBill:
In the last days i read a lot about VSS and GC . Thank you for providing so much information
and your VSS free version.

I did a test render scene with VSS : 2 figures (Behemoth, PuzzleCube) and a prop (a column)
So VSS created the shader nodes for the human figure - an improved Shader generated by the VSS System with Material AO and GC.
The Column prop and the PuzzleCube Figure dont have Shaders with Material AO and GC

Shouldn't the other Figure and the prop have Material AO and GC too ?

(Didnt work to get a small version of the pic in here, so the link is:)
http://www.renderosity.com/mod/gallery/index.php?image_id=1827173

My question is :
? How i can integrate a generic material AO and GC shader into VSS
to apply it to for example to the PuzzleCube fiugre and the Colum (Prop), or any others ...
(RTFM: yes i read the VSS Docu, but i am just starting with it)

Greetings
xuu4u

Initially, the construct of the VSSProp only target human figures and other creatures with some modification. That is all covered in the 'manual' to some extent. You have not mentioned which version of Poser you are using, so it would be difficult to instruct you on how to proceed. And there are other threads in the forum which also address similar situations. In Poser 7, you would need to create the appropriate nodes for AO and GC in the material room. However, PoserPro has GC built into it's render engine, eliminating the need to create GC nodes. It is also suggested for PoserPro to use light-based AO rather than introducing it into the material. There is a better affinity towards accuracy not seen in Poser 7.

I just always lower the gamma to 1.

Attached Link: http://www.renderosity.com/mod/forumpro/showthread.php?thread_id=2737823&page=27#message_3268316

> Quote - @BagginsBill: > In the last days i read a lot about VSS and GC . Thank you for providing so much information > and your VSS free version. > > I did a test render scene with VSS : 2 figures (Behemoth, PuzzleCube) and a prop (a column) > So VSS created the shader nodes for the human figure - an improved Shader generated by the VSS System with Material AO and GC. > The Column prop and the PuzzleCube Figure dont have Shaders with Material AO and GC > > Shouldn't the other Figure and the prop have Material AO and GC too ? > > My question is : > ? How i can integrate a generic material AO and GC shader into VSS > to apply it to for example to the PuzzleCube fiugre and the Colum (Prop), or any others ... > (RTFM: yes i read the VSS Docu, but i am just starting with it) > > Greetings > xuu4u

The link above will take you to the page in the VSS thread where I show how to customize a control prop for a horse. The same technique is used for any prop or figure.

First you must decide what are the various materials you want VSS to distribute. Suppose you are working with a chair that has leather upholstery, a cloth throw pillow, and some wooden legs. So you'd need 3 new real-world materials - Leather, Cloth, Wood. It doesn't matter how many material zones those have to be spread out on, there are only 3 distinct shaders you'll be using. You then use the VSS Designer buttons to create a Template for each of those shaders. You'd then load shaders into the templates.

Next you need to add some rules that associate the material zones on your prop or figure to the templates you created. These are in the Shader Rules material of the control prop. Suppose the chair has multiple material zones for the leather, such as Front, Back, and Sides. You'd need to create a rule for each of those that copies the Leather material onto them. Another rule would copy the Wood shader to the Legs material zone. And if you had two pillows, PillowLeft and PillowRight, you could right one or two rules to copy the Cloth shader. For example Rule pillow* Copy Cloth would work for both.

Finally you need to customize the control prop to know what scene elements to work on. These are in the Apply Rules material zone on the control prop. Suppose you have two charis, named Chair_1 and Chair_2. You could add a Rule chair* to match all chairs, or you could put specific chair names in. If you use the chair*, then when you add two more chairs, Chair_3 and Chair_4, VSS would automatically apply this control prop to those new chairs.

It is up to you whether you want to make a brand-new control prop for each type of item you work with, or just have a single prop handle everything in your scene. Any prop will do as a control prop, as long as it has material zones called Apply Rules and Shader Rules. The VSS designer buttons will help with this task.

The only reason I'm using nodes to express all these rules is because Poser doesn't have a solution to my need for a nice, easy-to-use GUI. I've shoe-horned all this functionality into this strange scheme so that I could give you a way to do all this using only simple dialogs that ask one question at a time. It's not the fastest way to do it, but it does get the job done. I'm working on a better way to provide a nice GUI. In particular, the Shader Rules as nodes lets you look over your rules in a pretty easy way. It's not so easy to make new rules, but it's very easy to understand what the rules actually are.

As for the actual shaders, that's another topic. I and others (ice-boy) have linked to threads discussing how to build new shaders that have GC in them.

It is my intention to someday provide a library of nice GC materials, ready to use. But I have a few issues to work out before I do that.

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Thank you very much for that detailed answer Bagginsbill.
I will read it carefully again und see what i can achieve.
BTW i use Poser7SR3.
English is not my mother language so forgive me my mistakes:)

Today i was looking the video at the poser7 pro tutorial site about
GC in Poser7 Pro.
(The sitelink was mentioned by BB, dont remember the thread)
I tell you, its worth looking it !!!. (runs only 6 min.y)

Presenting my understanding of GC here (some guesses, pls correct me if i am wrong)

GC in Poser7 Pro
The most stuff created on the pc like texturemaps has a burntin gamma of 2.2
what means is non-linear color space.
The renderegine of Poser7 Pro like other apps (maya, XSI etc.) works in
linear color space.
Therefore Poser7 Pro offers you GC (manually or global) for that stuff, before it goes
to the renderengine. (nonlinear to linear colorspace)
And after the render is finished, poser7 pro GC's the result again
(linear to nonlinear colorspace) with a gamma value of 2.2
(Provided that you switched GC on)

The reason is because on the pc the displaying devices (monitors, graphic-cards)
are built for a Gamma Value 2.2 (like digital cameras too)

I guess, no i am sure, the renderengine of Poser7 renders even so in linear color space,
and that is the reason bcause the renders looks so 'wrong' or to dark, and we
try to correct this with increased light settings.

GC in Poser7 with VSS and the GC Lens.

There was no GC inside Poser7 (P4,P5,P6), untill BB created VSS.

The GC included in the skin shaders generated by VSS takes care of the 'in part'
to the renderengine, means nonlinear to linear color space GC by a value of 2.2
The template skin shaders included in VSS (free version) supports human figures (SKIN)
(Remember that you can do lot more with VSS )

The results of using VSS generated skin shader on human figures are drastically improved renders, they are not so dark and need less lighting values.

To be as constant as Poser7 Pro we have to use also the GC Lens prop
to simulate the 'out Part' (GC for the Resulting Pic, linear to nonlinear with a gamma of 2.2)
The CG lens has to be used meanwhile the renderengine of Poser7 is running !!!
(Ohterwise you want put GC Nodes to Surfacenode by hand)
.........

Following BB's instructions i had my first success with GC today:
Connecting the GC Nodes to Kozaburos Long Hair Evolution.
Together with VSS for the skin i got great results. (Me happy :)
For this hair to work correctly you have to check the normals_forward in the
rootnode for every materialzone and don't use the rendersetting remove backface polys.
(thats what i learned in a BB forum thread :))
I am still working on this Pic und will post in some days in my gallery.

BTW did you know that using the GC Lense corrects the forward_normals problem
of the hair also :)

I tried the GC Lens with different settings, but honestly i like mor the results
without the Lens.

Greetings
xuu4u

You had everything correct until you spoke of the lens.

My GC shaders ALSO perform the final gamma correction. The GC shaders do exactly what Poser Pro does - they correct GC in and out. There is no need to use the lens with GC shaders. If you do, you will double correct the final result. If you wish to use the lens with GC shaders, you must re-design the GC shader to skip the final GC out step.

For the same reason, you must not use GC shaders in Poser Pro when you have render GC turned on.

I offered the GC lens as a way to GC an entire scene, without the need to use GC shaders.

But if you are sophisticated and patient and willing to work, the GC shaders are much better than the GC lens. If for no other reason, you have more control.

The GC lens is a good solution for people who have no patience to manually change all materials, even with VSS.

Also, let's be more clear about the Poser version names. There is no "Poser 7 Pro" as you called it. It is called Poser Pro. There is Poser 7 and there is Poser Pro.

Your English is excellent. You have no need to ask for us to excuse it. :)

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@bagginsbill:
Thank you for your fast answer and correcting my mistake.
I am glad that there was only the mistake about the lens :)
Reading so much threads (the big VSS one has 58 pages) about VSS,
shaders and GC i was a bit confused.
But now i am happy with the output i get from VSS and i know how the basic things
concerning VSS GC and the GC Lens belongs together.
Time to get deeper into VSS and Matmatic is also waiting for me :)

happy greetings
xuu4u

ps: BB you are programming VSS in python. I found a way how to run IDLE (mini gui and working debugger) Inside Poser7. Mybe this could be helpful for you .
Some days ago i wrote a quick tutorial how to do this.
Part1
http://www.renderosity.com/mod/tutorial/index.php?tutorial_id=2222
Part2
http://www.renderosity.com/mod/tutorial/index.php?tutorial_id=2223

Mr Billbaggins, is the VSS release which i see in your site free stuff under random shaders THE VSS ??? Want to make sure I am downlaoding the right thing

Thanks

______________________

"When you have to shoot ...

SHOOT.

Don't talk "

- Tuco

Santicor's Gallery:

http://www.renderosity.com/homepage.php?page=3&userid=580115

VSS, the software, and the original shaders and lights as well as Preview Release 2 control prop containing new shaders are on the VSS Home Page:

http://poserbagginsbill.googlepages.com/vsshomepage

I have another, larger site here:

http://sites.google.com/site/bagginsbill/

The item in random shaders:

http://sites.google.com/site/bagginsbill/free-stuff/random-shaders

is the Preview Release 3 skin shader.

Basically the original software, lights, and control prop is PR1.

Just a new control prop is PR2

Just a new skin shader (3rd skin shader) is PR3

So install PR1, then PR2, then make a new improved control prop yourself with the PR3 shader.

Or mix and match. There is no reason you should like and use only one.

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Brilliant, thanks Bagginsbill -
there are so many shading threads here and there, and then they get referenced within eachother and it's possible to lose your bearings over what is going on and what is the newest info you are reading !

RENDO should create a forum in the topics section called "SHADING IN POSER"

______________________

"When you have to shoot ...

SHOOT.

Don't talk "

- Tuco

Santicor's Gallery:

http://www.renderosity.com/homepage.php?page=3&userid=580115

by GC shader, you're talking about VSS, right?

Quote - by GC shader, you're talking about VSS, right?

VSS shaders are GC (optional) shaders. But I wasn't talking specifically about them.

I have posted many other GC shaders, that are not part of VSS. Mostly showing people how to do GC.

You can turn the GC off with a single parameter in my VSS shaders. VSS has GC shaders for skin, sclera, iris, gums, and teeth.

But I have made other GC shaders of metals, water, glass, plastic, paint, stone, wood, tile, brick, stucco, cloth, paper, mud, blood, hair, nailpolish, glitter, ... more.

I am holding them back - not released yet - because of ... BZZZT ... [ can't talk about it ].

Renderosity forum reply notifications are wonky. If I read a follow-up in a thread, but I don't myself reply, then notifications no longer happen AT ALL on that thread. So if I seem to be ignoring a question, that's why. (Updated September 23, 2019)

Quote - Brilliant, thanks Bagginsbill -
there are so many shading threads here and there, and then they get referenced within eachother and it's possible to lose your bearings over what is going on and what is the newest info you are reading !

RENDO should create a forum in the topics section called "SHADING IN POSER"

There used to be a lot more traffic at RuntimeDNA in the Poser forum. I used to write just as much there as I do here.

A bunch of people made the same observation. Very confusing to try to follow me around from thread to thread. So RDNA made a new forum just for me.

That forum is the Node Cult. It is strictly for shaders. Not discussion of modeling, or how to use certain products. Just shaders.

Hardly anybody goes there (RDNA forums) anymore, so I hang out here at Rendo a lot more. I think it's partly because the search engine sucks over there, so nobody can find anything.

If you want to learn tons more about shaders, read every single thread at the Node Cult. Then post your questions there so others can learn.

Or here, I don't really care. It's Acadia who has to put all the links to shader threads together.

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GC is a simple concept , pretty basic node set up, but extremely Affective and Effective...

I'm finally doing it as a result of Bagginsbill's guidance in this thread and the difference is staggering. I don't render like a shmuck anymore.

______________________

"When you have to shoot ...

SHOOT.

Don't talk "

- Tuco

Santicor's Gallery:

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Quote - I am holding them back - not released yet - because of ... BZZZT ... [ can't talk about it ].

Poser 8?

My apologies if I missed the answer to this, but so much of the shader node talk just goes zoom over my poor little head.

I have a favourite skin that I love to work with (RMTH Bianca Combo), but every time I turn on GC in Poser Pro, she renders grey. The eyes and lips are fine, but her skin is a sickly grey. Is there something I need to turn off or on in order to fix it? I've tried running the python script to change everything from 2.2 to 1, but that does nothing to solve it. And I'm not sure where to even start playing in the materials room.

Is this a common problem with a simple fix? Or is there a patient explanation somewhere of what to do to fix it? Thank you!! :)

lady-morana.deviantart.com

Quote - > Quote - by GC shader, you're talking about VSS, right?

But I have made other GC shaders of metals, water, glass, plastic, paint, stone, wood, tile, brick, stucco, cloth, paper, mud, blood, hair, nailpolish, glitter, ... more.

I am holding them back - not released yet - because of ... BZZZT ... [ can't talk about it ].

ohhh come on man. give us a teaser :) a teeeeaser

Oh boy, I'm not surprised there is a problem. That is such a fair skin and it has a shader on it.

So one of the problems with Poser Pro GC is that all the node parameters that are colors are interpreted differently.

When you enable render GC in Pro, it assumes every color that was chosen for a parameter was based on how it looked to the person choosing the color. However, there are situations where color parameters are used as data, not a color.

For example, if there's a place where a 30% gray value is used to control the influence of some other data, Poser Pro thinks you wanted something that LOOKS like 30% gray on your screen and it anti-gamma corrects that to a 7% gray. This will cause all sorts of problems.

I cannot help with the specifics unless I looked at the shader. RM uses some pretty tricky shaders lately.

I'd say show me the shader, but that might be a TOS violation, to publish a shader from a commercial product. There are some people who think that shaders aren't copyrightable. I think that's wrong. If I give you a shader with 400 nodes in it (and I've done such) I'd say that's just as copyrightable as a 400-line Python script.

Anyway, why not contact the vendor(s) and see if they can either help, or give you permission to show me the shader, so I can help.

I'm sure that if I saw the shader, I could fix it.

Renderosity forum reply notifications are wonky. If I read a follow-up in a thread, but I don't myself reply, then notifications no longer happen AT ALL on that thread. So if I seem to be ignoring a question, that's why. (Updated September 23, 2019)

Quote - > Quote - > Quote - by GC shader, you're talking about VSS, right?

But I have made other GC shaders of metals, water, glass, plastic, paint, stone, wood, tile, brick, stucco, cloth, paper, mud, blood, hair, nailpolish, glitter, ... more.

I am holding them back - not released yet - because of ... BZZZT ... [ can't talk about it ].

ohhh come on man. give us a teaser :) a teeeeaser

That was a teaser. :) What is it you want, renders? Or samples?

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renders are fine

Quote - > Quote - > Quote - > Quote - by GC shader, you're talking about VSS, right?

But I have made other GC shaders of metals, water, glass, plastic, paint, stone, wood, tile, brick, stucco, cloth, paper, mud, blood, hair, nailpolish, glitter, ... more.

I am holding them back - not released yet - because of ... BZZZT ... [ can't talk about it ].

ohhh come on man. give us a teaser :) a teeeeaser

That was a teaser. :) What is it you want, renders? Or samples?

he he he i know that this was teasing.
you dont need to show renders.

cloth and hair is interesing. have you find a way to make more realistic hair specular?

Quote - have you find a way to make more realistic hair specular?

No - I did some work on that, but it doesn't come out right. The Poser Anisotropic specular node is not adequate, but it is close. To do it right, I need a new node kind of shader node. If there was some way to add new kinds of nodes to Poser, that would make it possible. Hmmm, what a concept.

In other hair, I'm working on procedural eyelashes, eyebrows, stuff like that. You may have seen it on the Antonia figure. Procedural hairs can be adjusted using numbers, and applied to any figure. Very handy.

Also, I have many layer effects for skin shaders. One of them is body hair - takes a transmap, but I'm working on procedural for that too.

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Here is a render with two of my new GC materials; light brass and polished granite.

Both have color parameters to let you create an infinite number of variations. The granite pattern is procedural.

In addition to GC, the granite features Fresnel reflection falloff.

Click for full size.

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since for poser we a lot of times use modeled hair with transmaps it would make sense if they would make a ''fake'' specular for hair.

for example i modeled a hair prop for apollo.its impossible to get now the specular right.
like i said since 80% renders have transmapped hair it would make sense if they would make a special hair node.

for skin i would ask you something. how many layers of specular do you think is good? i am now testing some shaders of you with my changes. i read on a CG forum that skin should have at least 2 specualr layers. one on the whole body and the second for glossy effect on specific parts.

Two layers is one way to do it.

But what I found is that a single Blinn does it all. You just have to modulate 3 parameters simultaneously.

Specular effects are always reflections of the light source at the boundary between air and skin, or liquid on top of the skin (oil or water). Most areas of skin are dry and rough (microscopically) so the reflection smears out and gets dimmer. But some areas, such as the nose, are more wet, and thus are smooth. When I say smooth, I mean microscopically, like 100 times smaller than a single pore. The pore itself is still a factor, and so are the small bumps on the skin. These are effects that can be seen explicitly with the naked eye, and should be included in the bump map. The micro stuff should be handled in the shader.

So I have a single number I call "shine". This number drives all three inputs to Blinn. Then I make a shine map. With a good bump, and the correct variations in shine across the shine map, it looks good.

When shine is high, eccentricity drops and reflectivity goes up, and rolloff drops a bit.

Some version of that is in the VSS PR3 skin shader, although that version is not perfect.

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Here's another angle on the table, and this time gold on the candlestick.

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i think the only thing that is off is the specular . but that is nto your fault. wwe dont have HDR specular. this is what we need for reflection.

Wait - you said specular, then reflection. These are two different effects.

Are you talking about the reflection of the scene in the table? Or specular reflections of my lights? I only have two very weak spotlights here. Most of the light is IBL. Specular effects are HDR in Poser, but not connected to the IBL. That's a problem. But usually I handle that by setting up my environment sphere to match and using HDR on that. Only problem is for strongly blurred reflections. I don't have a good solution for that. That's why I'm doing polished granite and metals. Easy.

The reflections are of the environment sphere, and that has an LDR panorama on it in this render, so yes it's weak. But if I put an HDR image it would pop. However, I don't have any good HDR from a home interior. So I used LDR here.

Here's another granite.

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Here is another newbee question:
how to gauging the gamma value of any poser stuff. e.g. texturemap ?
can i measure it with gimp ?
if the gamma is 2.2 just use VSS
what to do if the gamma is less , or i have a texturemap with alread linear coloar space ???
(normaly not on pc i guess :))

expecting answers

greetings
xuu4u

I suppose it is possible somebody has a JPEG in linear format, but I doubt it. Officially, all JPEG and PNG files are in sRGB color space, with a gamma of 2.2.

So you don't need to judge a texture map to see if it needs GC. It does.

You can't "measure" it because you have to know what it should be in order to tell how it was encoded. If there is a pixel of value .5 in an image, should it be .5 or .5 ^ 2.2? According to the spec, the luminance of a .5 pixel in a JPEG file is .5 ^ 2.2, not .5.

If it is a photo, and it looks normal, then it is surely sRGB. Any photo texture, such as a rock or brick, is in sRGB color space and the numbers do not directly represent luminance, so should be un-gamma corrected on the way into the shader.

If you do have something where the gamma is less, you can change the shader to deal with it. Basically the processing of an image coming into the shader is to simply apply the right exponent to it. In all my VSS shaders, this exponent is in a math node and is 2.2.

If you want the incoming gamma to be different - for example, 1.5, then you must separate that node because it is also used for outgoing final gamma correction. Where that is done is in a divide node where I connect to the same 2.2.

If you disconnect it there, then put the 2.2 in the divide node Value_2, then you have separate gamma in and gamma out. Then you can use 1.5 on the gamma in, and 2.2 on the gamma out.

Renderosity forum reply notifications are wonky. If I read a follow-up in a thread, but I don't myself reply, then notifications no longer happen AT ALL on that thread. So if I seem to be ignoring a question, that's why. (Updated September 23, 2019)

Quote - Wait - you said specular, then reflection. These are two different effects.

Are you talking about the reflection of the scene in the table? Or specular reflections of my lights? I only have two very weak spotlights here. Most of the light is IBL. Specular effects are HDR in Poser, but not connected to the IBL. That's a problem. But usually I handle that by setting up my environment sphere to match and using HDR on that. Only problem is for strongly blurred reflections. I don't have a good solution for that. That's why I'm doing polished granite and metals. Easy.

The reflections are of the environment sphere, and that has an LDR panorama on it in this render, so yes it's weak. But if I put an HDR image it would pop. However, I don't have any good HDR from a home interior. So I used LDR here.

Here's another granite.

i mean HDRI reflections. you know when you have plastic or car paint. the brightest parts are brighter in the reflection. for example windows,.......

OK. So in case somebody else is reading this, they might be confused.

We do have HDRI reflection capability in Poser. I just didn't use an HDR on my e-sphere here because I didn't have one.

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poser pro supports this???????????????????????????????????????????????????????????

bagginsbill poser pro supports NOW specular reflection?

how...when.............what?????????

Poser 7 supports it. And you just changed back to saying "specular" reflection. Say scene reflection.

Specular effects (Blinn, Anisotropic, etc.) are simplified models of reflection (in Poser) and only consult your directional lights.

Poser's ray-traced reflection (Reflect node) does not consult your lights, but rather what is in your scene. That is what you just demonstrated and what I was demonstrating.

In other CG apps, the "specular" effects include BOTH the influence of your light sources and your scene. And they also include the influence of your Image Based Lighting. Poser does not include this in anything except the Diffuse effect.

But by using my environment sphere, you can include the IBL image data as reflection data, for use in specular reflection. That is the point of my environment sphere. And I said all along that you can put an HDRI on the e-sphere. That's why the e-sphere shaders have a gamma-in parameter. If you've attached an LDRI, you use 2.2 for gamma-in. If you've attached an HDRI, you use 1.0 for gamma-in.

You can do this in either Pro or 7. All you need is e-sphere.

Renderosity forum reply notifications are wonky. If I read a follow-up in a thread, but I don't myself reply, then notifications no longer happen AT ALL on that thread. So if I seem to be ignoring a question, that's why. (Updated September 23, 2019)

aha

you also said that you have some new GC cloth shaders. what kind of specular do you use? i never know what settings to use there.
can you show a render?

thanks.

at last, some good news on poser 8. from one of the msgs on page 2 of this thread, we may deduce that:

they are proceeding apace with poser 8 alpha
SM didn't sell poser to another software company
poser 8 beta is just around the corner

People throw these "alpha" and "beta" terms around pretty freely. Let me make sure you know what they mean, because nobody said anything that would let you conclude they are in alpha.

Alpha is when all software features are frozen - no new features under development, just testing.What gave you the idea that's where they are?

Some companies make alpha internal testing only. Others let customers have it for alpha.

In any case, beta is when you think it's really done and now you're working out the problems in rolling out and supporting the product. Customers should generally not be finding major things wrong in Beta, except with manuals and installation procedures, etc.

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bill, thx fr the clarification on the alpha and beta. what do they call the version prior to the alpha -
e.g. the phase in which they were still entertaining suggestions in regard to replacing or
improving FFRender with various GUIs and new features?

anyway, it appears congratulations are in order in regard to the inclusion of your GC shader items
in a soon-to-be-released product, possibly even poser 8 itself.

What? I never said any such thing.

All I said was BZZZT.

And by that I meant that I am in some planning/discussion to finally produce something commercially, and I did not want to disturb that process by saying anything I should not say.

But then why did I say anything? Because I'm constantly bombarded with questions like "Why don't you sell your stuff?" "Where can I buy your stuff"

Please don't spread any rumor like that. It will cause trouble, whether it is true or false.

And please don't congratulate me - my track record is I never finish ANYTHING related to Poser. Ever. What have I ever finished?

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Quote - bill, thx fr the clarification on the alpha and beta. what do they call the version prior to the alpha -
e.g. the phase in which they were still entertaining suggestions in regard to replacing or
improving FFRender with various GUIs and new features?

That doesn't have such a standardized name, but it is most commonly called "requirements gathering" or "needs assessment" and it happens all the time, even if there is a current project going out the door.

Usually at the official beginning of a "next release" project, lots of people get in a room and argue for days about what features and functions are going to be in or out of this release. Depending on which PDP you follow (Product Development Process) you may call this Define, Definition, Project Definition, etc.

The Product Development team usually follows something like this (cleverly alliterative) sequence:

Define -> Design -> Develop -> Deploy

Where is Test in all that? There's no synonym for Test that begins with D. This is why most product development teams do very littlte testing. :)

But seriously, because Software "Developers" do the Develop step, they believe that testing is part of Deploy and has nothing to do with them. That's why a lot of software sucks ass.

Some will tell you that test is part of Deploy, but that's really Beta Testing. Alpha Test (and sometimes there is an official pre-Alpha testing phase) go before that. So the true sequence is:

Gather Requirements -> Define -> Design -> Develop -> Test -> Deploy

In my organization, Developers have to constantly develop tests along with there code, or I kick their asses. Unit tests, regressions tests, performance tests, smoke tests. All these, along wiht the program itself, go to QA as deliverables, i.e. the tangible outcome of the Develop phase.

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interesting read.

you are a beta user for poser right?

BB was beta tester for Poser Pro. But that does not mean he knows something about Poser 8.

These are not the droids you're looking for. You can go about your business... Move along.

A ship in port is safe; but that is not what ships are built for.
Sail out to sea and do new things.
-"Amazing Grace" Hopper

Avatar image of me done by Chidori.

well they should listen to him. after all he is one of the main reason people here like poser so much. without him poser renders would be more fake.

I'm a convert to gamma correction. Totally. Did the material CG thing on a scene - took me upward of three hours, but it's done. I went from this (rendered using 4 lights, all except IBL at 100% or above):

to this... two lights, Infinite at 60% and IBL at 12%:

Now, I'm going over all my favourite scenes (pz3s) and applying GC to the materials. Good job I have Matmatic and VSS - this would be a nightmare to continue doing it all manually.

I only found out about GC not long ago, but boy-howdy, I'm a devout convert. Got a blog that discusses it:
tightbytes.com/wordpress/
Not going to pretend I got it all right - feel free to leave comments and corrections - but so far it's been such a dramatic improvement... it's like someone got me a new version of Poser.

Thanks SO much, BagginsBill!

Monterey/Mint21.x/Win10 - Blender3.x - PP11.3(cm) - Musescore3.6.2

Wir sind gewohnt, daß die Menschen verhöhnen was sie nicht verstehen
[it is clear that humans have contempt for that which they do not understand]

Metaphor of Chooks

That second image, I would say, is about mid day. The Infinity lighting is a bit harsh and the shadows intense. It is actually perfect for the lighting application you are using along with the GC. Good Job!

BTW, I just very quickly checked out your blog and I am impressed. Unfortunately, I will carefully digest it at another opportunity when I have more time. However, I noticed that your background objects are lacking any displacement to elevate the fine detail. At least, that is what I discerned from your shader node images. It may bring a little more life into the scene. Also, which version of Poser are you using? As you are aware, PoserPro has introduced GC within it's application. And I am wondering if material based GC may cause additional problems with corrected renders on sRGB monitors.

I noticed the flat look as well, Hborre. I tried plugging into the displacement channel with the same values, but it didn't improve matters any - need to create an actual displacement map: the creators of this scene were using the colourMap (ImageMap jpg) instead of a dedicated greyscale displacement map. BTW, I did plug the colourMap directly into the bump (and tried displacement) channel as it had been before GC:

Render settings included min displacement (.008) and raytracing on.
Lights: two...

Main Infinite Light… map size (1024) rgb (1,1,1) intensity (60%) ray-traced, shadow blur radius (6.0) min bias (0.2) …nil AO

IB Light…………… map size (256) rgb (1,1,1) intensity (12%) nil shadows, nil AO

Monterey/Mint21.x/Win10 - Blender3.x - PP11.3(cm) - Musescore3.6.2

Wir sind gewohnt, daß die Menschen verhöhnen was sie nicht verstehen
[it is clear that humans have contempt for that which they do not understand]

Metaphor of Chooks

I can understand that frustration. Recently, I loaded an old model into Poser and discovered that the image_maps were not Gamma Corrected also with no displacement. A dungeon scene with stone walls. I Gc'ed the maps in Photoshop, and once I brought them into Pose, created grayscale displacement maps by plugging the Image_maps into a hsv node. The saturation value was turned down to 0. This node was plugged into the displacement channel. Upon rendering, I had to remind myself to turn on displacement in the render settings.

Thank you for that, hborre. I'm curious as to what technique you used to gamma-correct in Photoshop. I use the GIMP - can't afford Photoshop, since I'm poorer than dirt buying all this content off here! - so I'll try to follow your instructions to achieve a displacement map. I'm assuming the d-maps were greyscale, right? Or does that matter? My understanding is that the bump and displacement channels don't use the colour information of the image, so greyscale saves memory overhead and gives those channels only what they need...

Monterey/Mint21.x/Win10 - Blender3.x - PP11.3(cm) - Musescore3.6.2

Wir sind gewohnt, daß die Menschen verhöhnen was sie nicht verstehen
[it is clear that humans have contempt for that which they do not understand]

Metaphor of Chooks

Here is an article I stumbled across several weeks ago concerning tone and gamma correction. It details how to set Gc in Photoshop and GIMP. This is food for thought but very well written and very thorough.

http://www.ypoart.com/tutorials/tone/index.php

WOW, excellent article, hborre! Thanks heaps... printing this one out to read in bed. It's exactly what I was looking for... thanks again!

Monterey/Mint21.x/Win10 - Blender3.x - PP11.3(cm) - Musescore3.6.2

Wir sind gewohnt, daß die Menschen verhöhnen was sie nicht verstehen
[it is clear that humans have contempt for that which they do not understand]

Metaphor of Chooks

Robyn, have you tried to add the color map image to a math function node and setting that node to substract before plugging the math node into the root node's displacement and/or bump node?
It makes a gray scale copy of the image map.

===========================================================

OS: Windows 11 64-bit
Poser: Poser 11.3 ...... Units: inches or meters depends on mood
Bryce: Bryce Pro 7.1.074
Image Editing: Corel Paintshop Pro
Renderer: Superfly, Firefly

9/11/2001: Never forget...

Smiles are contagious... Pass it on!

Today is the tomorrow you worried about yesterday

Hmmm, that's worth a try. Thanks for the idea ThunderStone.

Thanks for your idea, Thunderstone... so in Matmatic that would be:

s = Surface()
s.Displacement = .012 * Color_Sub(ImageMap("MyColourPic.jpg"))

or, in nodal terms,

ImageMap -> Color_Math (Subtract) Value_1 -> PoserSurface displacement channel (.012)

Monterey/Mint21.x/Win10 - Blender3.x - PP11.3(cm) - Musescore3.6.2

Wir sind gewohnt, daß die Menschen verhöhnen was sie nicht verstehen
[it is clear that humans have contempt for that which they do not understand]

Metaphor of Chooks

Quote - Thanks for your idea, Thunderstone... so in Matmatic that would be:

s = Surface()
s.Displacement = .012 * Color_Sub(ImageMap("MyColourPic.jpg"))

or, in nodal terms,

ImageMap -> Color_Math (Subtract) Value_1 -> PoserSurface displacement channel (.012)

Nope it would be:
ImageMap -> Math_Function(Subtract) input 1 Value _1 ->PoserSufrace displacement channel (0.0012) I always make the displacement value smaller than the bump value but you got to tweak it according to your taste.

I don't think you can do subtracting with the Color_Math node....

===========================================================

OS: Windows 11 64-bit
Poser: Poser 11.3 ...... Units: inches or meters depends on mood
Bryce: Bryce Pro 7.1.074
Image Editing: Corel Paintshop Pro
Renderer: Superfly, Firefly

9/11/2001: Never forget...

Smiles are contagious... Pass it on!

Today is the tomorrow you worried about yesterday

Thanks for clarifying, Thunderstone. I'll have a go and see what I get.

Monterey/Mint21.x/Win10 - Blender3.x - PP11.3(cm) - Musescore3.6.2

Wir sind gewohnt, daß die Menschen verhöhnen was sie nicht verstehen
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Metaphor of Chooks

Here's the snapshot of the setting for just this purpose. Not gc or anything like that .... Just plain old illustration.

===========================================================

OS: Windows 11 64-bit
Poser: Poser 11.3 ...... Units: inches or meters depends on mood
Bryce: Bryce Pro 7.1.074
Image Editing: Corel Paintshop Pro
Renderer: Superfly, Firefly

9/11/2001: Never forget...

Smiles are contagious... Pass it on!

Today is the tomorrow you worried about yesterday

Thank you, Thunderstone. So... the purpose of filtering out colour information to the bump and and displacement channels with that Subtract node is to prevent erroneous info from getting to the channels? Just trying to get my head around it... I can see the validity of having one image serve two purposes: less memory overhead. Your method would provide the greyscale without the overhead.

I know that BagginsBill will shudder at this, but I'm using Matmatic in a way he probably didn't quite have in mind: as an efficient means of creating simple materials (read: retrofit) with GC. Whilst applying a GC mt5 to a material with one ImageMap is a no-brainer, some content developers are using a more sophisticated shader, like Fabiana in her Noctia dress, which takes a bit more to incorporate GC.

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Wir sind gewohnt, daß die Menschen verhöhnen was sie nicht verstehen
[it is clear that humans have contempt for that which they do not understand]

Metaphor of Chooks

hum, sorry but with all the nodes plugged to the alternate diffuse, you dont need plug your map on the diffuse color or only with a diffuse color white and a diffuse value 0, it's only to show the map in the preview !

Génération mobiles Le Forum / Le Site

That is the point of the diffuse_color connection. Many individuals would like to see what is happening with the scene while in preview mode. It is very hard to conceptualize a scene while staring at many blank objects.

That works for ImageMap, anyway. Haven't figured out a way to get node-based colouring to display... like in this shader:

Monterey/Mint21.x/Win10 - Blender3.x - PP11.3(cm) - Musescore3.6.2

Wir sind gewohnt, daß die Menschen verhöhnen was sie nicht verstehen
[it is clear that humans have contempt for that which they do not understand]

Metaphor of Chooks

Quote - Thank you, Thunderstone. So... the purpose of filtering out colour information to the bump and and displacement channels with that Subtract node is to prevent erroneous info from getting to the channels? Just trying to get my head around it... I can see the validity of having one image serve two purposes: less memory overhead. Your method would provide the greyscale without the overhead.

I know that BagginsBill will shudder at this, but I'm using Matmatic in a way he probably didn't quite have in mind: as an efficient means of creating simple materials (read: retrofit) with GC. Whilst applying a GC mt5 to a material with one ImageMap is a no-brainer, some content developers are using a more sophisticated shader, like Fabiana in her Noctia dress, which takes a bit more to incorporate GC.

Exactly just like those separate bump and displacement map will do. Also it serve if there is no bump or displacement and you don't want to go thru the expense of time and memory to create a new grayscale map. I think BB will have a fit with me also because some of the skins shaders do not have bump map and this method (I can't quite credit myself with but someone else came up with it (I think) I know I have seen it somewhere else. ) helps to give me a good realistic render.

===========================================================

OS: Windows 11 64-bit
Poser: Poser 11.3 ...... Units: inches or meters depends on mood
Bryce: Bryce Pro 7.1.074
Image Editing: Corel Paintshop Pro
Renderer: Superfly, Firefly

9/11/2001: Never forget...

Smiles are contagious... Pass it on!

Today is the tomorrow you worried about yesterday

I am having many fits here.

Let's play Socrates.

Given a value, x, what is 1 * x - 0?

Renderosity forum reply notifications are wonky. If I read a follow-up in a thread, but I don't myself reply, then notifications no longer happen AT ALL on that thread. So if I seem to be ignoring a question, that's why. (Updated September 23, 2019)

1 * Color_Map - 0

What value does that give you?

Another question:

Plugging a color into a numerical Math node parameter converts the color to gray scale. The Subtract node Value_1 is what I'm talking about here.

What happens if you plug a color into some other numerical node parameter. Suppose you plug it into Bump or Displacement. What is going to happen?

A related question: If I connected 500 of these Subtract(1 * x, 0) nodes in series, what would change?

Related to that, if I connect no subtract nodes here, what changes?

Renderosity forum reply notifications are wonky. If I read a follow-up in a thread, but I don't myself reply, then notifications no longer happen AT ALL on that thread. So if I seem to be ignoring a question, that's why. (Updated September 23, 2019)

Of course, I did not even begin to address whether this makes sense, from an image quality standpoints. At the moment, I'm just talking about the math.

What is 1 * 1 * 1 * 1 * 1 * x - 0 - 0 - 0 - 0 - 0?

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1 x ?

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Wir sind gewohnt, daß die Menschen verhöhnen was sie nicht verstehen
[it is clear that humans have contempt for that which they do not understand]

Metaphor of Chooks

Quote - Of course, I did not even begin to address whether this makes sense, from an image quality standpoints. At the moment, I'm just talking about the math.

What is 1 * 1 * 1 * 1 * 1 * x - 0 - 0 - 0 - 0 - 0?

x-0 which is the same as x=0 hence nonsensical answer or zero (0)....

===========================================================

OS: Windows 11 64-bit
Poser: Poser 11.3 ...... Units: inches or meters depends on mood
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Image Editing: Corel Paintshop Pro
Renderer: Superfly, Firefly

9/11/2001: Never forget...

Smiles are contagious... Pass it on!

Today is the tomorrow you worried about yesterday

x-0 is not 0 it's x agggg!

x - 0 = x
1 * x = 1x
Right? Sheesh, I suck at math....

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Wir sind gewohnt, daß die Menschen verhöhnen was sie nicht verstehen
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Metaphor of Chooks

err unless x=0 then x-0 would be 0

Since x stands for some unknown value, subtracting 0 from x will leave x, whatever that value might be.

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Wir sind gewohnt, daß die Menschen verhöhnen was sie nicht verstehen
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Metaphor of Chooks

What I am missing is a good understanding of doing math on colours. Yes, if you break them down to tuples and then subtract, it makes sense. But connecting a pure math node (add / subtract / whatever) to an image leaves me in the dark still as to what exactly is going on.

What was being suggested was:

Surface.Bump = .0012 * Sub(ImageMap("MyColourPic.jpg"))

Sub in this case assumes Value_1 to be 1? and Value_2 to be 0? Which is the same as 1 - 0 = 1, which isn't doing anything?
Well, I plugged this all in as suggested and got the same image. Not trusting my eyes, I'm waiting for a better way to 1. validate that this way is erroneous and 2. create a greyscale image for those channels. Or do the channels just use what they need and ignore colour information anyway?

Monterey/Mint21.x/Win10 - Blender3.x - PP11.3(cm) - Musescore3.6.2

Wir sind gewohnt, daß die Menschen verhöhnen was sie nicht verstehen
[it is clear that humans have contempt for that which they do not understand]

Metaphor of Chooks

OK somehow the Socratic method failed.

You were supposed to make the following conclusion.

x - 0 = x

Using words, subtracting 0 from a quantity does nothing to that quantity. You are wasting your time calculating x - 0.

Does that help you understand my point?

Renderosity forum reply notifications are wonky. If I read a follow-up in a thread, but I don't myself reply, then notifications no longer happen AT ALL on that thread. So if I seem to be ignoring a question, that's why. (Updated September 23, 2019)

I think a lot of the misconceptions and erroneous "solutions" we come up with is because we don't fully - or, in my case, don't hardly - understand how math works on images. I'm not speaking for the Ones That Know, but for those who don't, me being prominent among them. There is a distinct conceptual gap between seeing a math formula and its application to an image.
I'm not happy with "yes, I see that it works" because seeing is no longer believing, at least, to me that's true. When someone presents a concept, I want to know why. Here is where scripting nodes seemed to help a bit.
A bit.
It forms more of a connection to what is actually happening ... what are we doing to those colours.

What hasn't been gone over to my satisfaction about the method used to do gamma correction is this - and I can hear a collective groan, but hey, bear with me: I'm thick.

As I understand this, here's what needs to happen:
convert image to linear space
process image
return image back to sRGB before handing over to the renderer...

Considering this code:
colourMap = ImageMap("sweaterTx.jpg")
gamma = Add(2.2).labelled("Gamma")
gammaPow = Color_Pow(colourMap, gamma)

am I to assume that the Color_Pow() function somehow converts the image to linear space and then does the gamma math to it? Where is the conversion to linar space done?

Let's start there. I want it all to be really clear in my pointy little head, so I won't create bogus stuff like I have been.

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Wir sind gewohnt, daß die Menschen verhöhnen was sie nicht verstehen
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Metaphor of Chooks

I thought that's what I said.
x - 0 = x

IOW, you've done nothing. Was that your point?

Monterey/Mint21.x/Win10 - Blender3.x - PP11.3(cm) - Musescore3.6.2

Wir sind gewohnt, daß die Menschen verhöhnen was sie nicht verstehen
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Metaphor of Chooks

Quote - IOW, you've done nothing. Was that your point?

Indeed, that was my point. In this scenario, plugging the color map straight into bump and displacement would do exactly the same thing. The math node isn't doing anything at all that you wouldn't get without it.

Some people may think the math node is doing the conversion to gray scale. Well, it is, but not because it is a subtract 0. It is doing that because you plugged a color into a number. Building a math node just to have a number to plug into is a useless and confusing waste of time.

The bump channel is a number. Plug the color into the number straight away.

The displacement channel is a number. Plug the color into the number straight away.

Renderosity forum reply notifications are wonky. If I read a follow-up in a thread, but I don't myself reply, then notifications no longer happen AT ALL on that thread. So if I seem to be ignoring a question, that's why. (Updated September 23, 2019)

Hi RV... I have another post coming up about bump/displacement (unless bb gets there first, if he's still around) but in the meantime...

"Convert to linear (colour) space" == "Do the gamma math"
(It's one and the same thing).

The assumption is that the colour map is done in sRGB colour space. To convert this to linear colour space, you need to anti-gamma correct it, i.e. raise the colour values to the power of your variable 'gamma', or 2.2 in this case.

"If I were a shadow, I know I wouldn't like to be half of what I should be."
Mr Otsuka, the old black tomcat in Kafka on the Shore (Haruki Murakami)

Quote - am I to assume that the Color_Pow() function somehow converts the image to linear space and then does the gamma math to it?

Ummm. Gosh this is so difficult. I've seen this so many times in the last month.

I'm stumped and don't know how to answer, because the two-part question is actually two different questions, and the phrasing and coupling of these two parts either indicates a contradiction, or represents a severe misunderstanding. Meaning, if I answer your question, I will confuse some more.

So let me ignore your questions and re-state what I've said (and all the other links say).

Images you're getting from cameras are designed to be seen on a computer, using the sRGB standard.

Images coming out of your render should be designed to also be seen on a computer, using the sRGB standard.

The sRGB standard is not a linear representation of luminance. In sRGB, it is incorrect to assume that doubling the value of a pixel should cause it to be twice as bright.

The sRGB color space is not quite exactly a simple power relationship. But it is very close to that, and so we can work with Gamma Correction (GC) as our working model. Until you are comfortable with GC, it would only serve to confuse you to talk about the true 100% accurate specification of the sRGB space. (It requires considerably more math.) While straight GC is slightly wrong, it is 1000 times more wrong to do nothing at all.

Lighting calculations should be in linear space. It is correct when calculating a material's response to light that doubling the value of a pixel should represent twice the illumination. This is the fundamental principle of linear math - that x + x = 2x. It is the only kind of math that most people ever encounter. There are other kinds, and they are exceedingly difficult to manage. Anybody wanting to do any accurate shader/lighting work must do it linearly.

Therefore, when using images as data, we must convert them from sRGB to linear values. I often call this anti-GC, because the image you have was gamma corrected in order to end up non-linear. To bring it back to linear, you must do the opposite of that gamma correction, so want to anti-GC the image. The math is:

image ** 2.2

There's really no point in discussing any other gamma value, because any image you have has almost certainly been gamma corrected by the factor 2.2, whether it was hand-drawn or photographed. All discussion about the 1.8 gamm value for Mac has pretty much stopped - Apple has seen the futility of having two display standards in the modern Internet world where we all must share content.

Then we must calculate reflections (whether specular or diffuse) and refractions using the formulas that describe the universe. These formulas are all built on the fundamental premise that for any value x, whatever luminance that represents, 2x is twice that. This is necessary for things to work out conveniently, such as the simple fact that the effective diffuse reflection of a specific amount of illumination depends on angle of incidence, specifically on the cosine of the angle of incidence. Further that if I double the light intensity, the diffuse reflection also doubles.

Once all reflection/refraction modeling is complete, we end up with a linear color value after adding some things together. Before placing this into the image, this must be converted to the sRGB color space. We cheat, and use gamma correction. The formula is:

y ** (1 / 2.2)

Where y is the rendered color.

Renderosity forum reply notifications are wonky. If I read a follow-up in a thread, but I don't myself reply, then notifications no longer happen AT ALL on that thread. So if I seem to be ignoring a question, that's why. (Updated September 23, 2019)

Quote - 1 * Color_Map - 0

What value does that give you?

Another question:

Plugging a color into a numerical Math node parameter converts the color to gray scale. The Subtract node Value_1 is what I'm talking about here.

What happens if you plug a color into some other numerical node parameter. Suppose you plug it into Bump or Displacement. What is going to happen?

A related question: If I connected 500 of these Subtract(1 * x, 0) nodes in series, what would change?

Related to that, if I connect no subtract nodes here, what changes?

If you plug a color into the numerical Math node granted if it's a solid color the only thing that will happen is nothing, especially if it's in the displacement or bump node. If that's the effect you're going for, then it's better to leave it off. But if you want to add some "umph" into the existing texture that the creator so kindly forgot to provide the bump or displacement map, you can add a quickie bump or displacement node.
As for the 500 of these nodes in a series, I would imagine the effect to be negligible after the first 2 nodes (I don't know. I am not an expert like you, BB. Half of the information I've received about the mat room came from that lil noggin of yours. The rest from tips and experience. ).

===========================================================

OS: Windows 11 64-bit
Poser: Poser 11.3 ...... Units: inches or meters depends on mood
Bryce: Bryce Pro 7.1.074
Image Editing: Corel Paintshop Pro
Renderer: Superfly, Firefly

9/11/2001: Never forget...

Smiles are contagious... Pass it on!

Today is the tomorrow you worried about yesterday

I imagine it must seem to you as difficult as explaining why 1 + 1 = 2, Bill. However, this discussion has cleared up a question or two for me, so far. I need to break down your words into my words: your concepts into mine. I suppose it's called assimilation: if I can explain your concept in my own words, I prove that I understand it. So, at the risk of boring you to tears or further frustrating you, I'm going to rehash these concepts. And thank you for your patience.

Yes, there are some misunderstandings. A partial understanding is as bad or worse than a complete lack of understanding. This is what I'm trying to eliminate with this discussion.

I see an image as a collection of pixels / coloured dots. Each dot contains colour information that can be represented as a tuple. This colour information in jpgs and I imagine pngs and tiffs all conform to a standard called sRGB. when you bring these images up in an image viewer program or an image manipulation program, they are meant to display according to that sRGB standard.

I think I can get my head around the tuple / red-green-blue concept of a coloured dot, since I have a visual representation of that in the Microsoft colour picker tool. But, I suspect that the colour picker and sRGB are only remotely related.

So, whilst these programs manage to display an image brightly and appropriately, Poser manages it differently because it has to do calculations in it, which become prohibitively complex in sRGB. So, it manages the image in linear colour space.

Linear colour space. What exactly is linear colour space? Why the term 'linear'?

You must be able to see to what degree these concepts are nebulous, based on these questions.

Monterey/Mint21.x/Win10 - Blender3.x - PP11.3(cm) - Musescore3.6.2

Wir sind gewohnt, daß die Menschen verhöhnen was sie nicht verstehen
[it is clear that humans have contempt for that which they do not understand]

Metaphor of Chooks

Quote - Images you're getting from cameras are designed to be seen on a computer, using the sRGB standard. Images coming out of your render should be designed to also be seen on a computer, using the sRGB standard. The sRGB standard is not a linear representation of luminance. In sRGB, it is incorrect to assume that doubling the value of a pixel should cause it to be twice as bright.

Ah, a clue. sRGB is a representation of luminance? just not 'linear'... which I take to mean: on a grid, the line would be straight from one point to the next. So, do I take it to understand this is what is meant by linear colour space? a means where doubling the value of a pixel does cause it to be twice as bright?

So, gamma is all about brightness, not colour. Well, I did say I was thick. Of course it's about luminance. The renders are dark. So, we're taking an image and converting it from some curved to straight luminance value. When I think "picture" I think colour, not luminance. Yet, this is what most people fail to understand: how important proper luminance management is.

Now, armed with this concept, let's look at the rest of your explanation.

Monterey/Mint21.x/Win10 - Blender3.x - PP11.3(cm) - Musescore3.6.2

Wir sind gewohnt, daß die Menschen verhöhnen was sie nicht verstehen
[it is clear that humans have contempt for that which they do not understand]

Metaphor of Chooks

Quote - The sRGB standard is not a linear representation of luminance.

Wait, so in linear space it is? Luminance! This is not about colours, it's about Luminance! So, in an image there's colour information and there's luminance information - that's needs to be converted! Right? Am I *anywhere near the right track, here?

One definition I found via googling for linear colour space: a color space in which the relationship between a pixel's digital value and its visual brightness remains constant (linear) across the full gamut of black to white.

However, CRT technology doesn't work that way:
The most important point to consider here, is that if the normalized voltage (normalized meaning the voltage can go from zero volt to one volt maximum) on the CRT electron gun is linearly increased from 0 to 1, the resulting brightness on the face of the CRT will not be perceived as linearly increasing. It will look like it takes time to get out of black and then suddenly becomes white. Looking at the 2.5 gamma graph above, it can be observed that the voltage needs to reach 75% in order for the CRT to output 50% intensity.

It appears that the luminance value going stepping from black to white on a non-gamma tube stays quite low (dark) for a while before going suddenly to quite high (bright). All has something to do with the relationship between brightness and output voltage of a CRT.

I think I understand now what I need to understand about the reason for gamma correction. The missing link was something obviously stupid: I was thinking colour, when I should have been thinking luminance.

Quote - In sRGB, it is incorrect to assume that doubling the value of a pixel should cause it to be twice as bright.

But in linear colour space - maybe they should have called it the linear luminance space, IF I'm getting this right - you can do that sort of math and at least be a little closer to your desired outcome.
Before I go barking up any more trees, this needs to be confirmed: is luminance the component of an image we are converting from sRGB to linear colour space? Is it a discreet component? or is it something that has to be calculated from the colour pixels themselves?

Don't you just HATE all these questions?

Monterey/Mint21.x/Win10 - Blender3.x - PP11.3(cm) - Musescore3.6.2

Wir sind gewohnt, daß die Menschen verhöhnen was sie nicht verstehen
[it is clear that humans have contempt for that which they do not understand]

Metaphor of Chooks

The luminance we're talking about is not the overall luminance, but the luminance of each color component in R, G, and B. Note, though, for a strictly gray-scale image those are the same thing and most explanations of GC try to demo it with shades of gray.

Your screen pixels comprise three components. In each pixel, one is red, one is blue, and one is green. The color you percieve for that pixel is controlled by the amount of red luminance, green luminance, and blue luminance, combined. The luminance is controlled by the voltage applied. The voltage is controlled by the numbers we store in each pixel component. The ratios of these RGB luminances within a pixel give rise to various hues and saturations.

GC is applied in order to produce the R, G, and B luminance calculated by our shaders/lighting model. Without GC, the intended luminance of each pixel is not actually produced - something darker is in all three components. Therefore the overall luminance is darker. But also, the overall hue and saturation is incorrect as well.

GC is directly about mis-represented luminance.

Mis-representations of luminance also produce mis-representations of hue and saturation.

Therefore, indirectly, GC is about hue and saturation as well.

Renderosity forum reply notifications are wonky. If I read a follow-up in a thread, but I don't myself reply, then notifications no longer happen AT ALL on that thread. So if I seem to be ignoring a question, that's why. (Updated September 23, 2019)

Good. Thank you. That is clear in my mind.

Next question.

Gamma correction is necessary only for image files used in a shader and only for diffuse or specular channels. [ T / F]

Since bump and displacement don't use colour information, it is not necessary to perform gamma correction on dedicated bump and/or displacement files, [ T / F]

or node-based colours and textures.[ T / F]

Monterey/Mint21.x/Win10 - Blender3.x - PP11.3(cm) - Musescore3.6.2

Wir sind gewohnt, daß die Menschen verhöhnen was sie nicht verstehen
[it is clear that humans have contempt for that which they do not understand]

Metaphor of Chooks

A confession: I've become shader-obsessed. I've been writing GC scripts to replace (and correct) more complex hair shaders and clothing shaders for everything in my closet. You wouldn't believe how many Specular_Value = 1 / Diffuse_Value = 1 shaders I see. They are going to throw me out of the forum I'm in because I won't shut up about GC. I think I need counselling.

Fortunately, I do have a blog... and will continue to share my experiences and conclusions and experiments there. The entries probably aren't completely accurate - I'd be happy with about 80% accuracy - but the results I'm getting are excitingly more vibrant and alive.
tightbytes.com/wordpress/

Forget about selling anything: I'm on a mission. And I haven't even played with AO, yet! When will it STOP??!?

Monterey/Mint21.x/Win10 - Blender3.x - PP11.3(cm) - Musescore3.6.2

Wir sind gewohnt, daß die Menschen verhöhnen was sie nicht verstehen
[it is clear that humans have contempt for that which they do not understand]

Metaphor of Chooks

Hi, RV. Following with interest still, but holding back on comments. Was expecting some guidance on displacement / bump maps and the "minus ~0.5" thing, but I guess that's for another time, since we're dealing with GC etc now.

I've developed a way of thinking about linear colour space, GC and anti-GC. It's nothing new or ground-breaking, just a way I found to think about it which helps me to grasp what I could not hold on to firmly before. That's why I've not said anything about it. It's possibly not even accurate, but it serves my purpose. It just involves doing the maths on numbers that proportionally represent actual light energy. I used my own (flexible but consistent) unit of measurement called "RGB photon-buckets" (at least, I've not heard that term anywhere else) to help me think it through. How many photons in a photon bucket? Well, how much water in a water bucket? Doesn't matter when you only count the buckets, but they must be all the same size. Ummm.... and full!

Anyway, what I really came here to say was... you mentioned in your latest blog (all of it read from start to finish, btw. You're doing good. No, that sounds patronising... I mean I think it's great stuff)... ummm, where was I? Yes, you mentioned that your purpose was to create a GC shader using Matmatic. Did you go off track? Because by the end of the page, I hadn't seen one line of ..... oh, wait, I stopped typing and went to have another look and saw your next section. hehe...

Just ignore me. Still, I'll let this go through so you know I'm here, reading with interest. You know, I think I could answer some of your questions, but it's getting so that I dare not. I'm like a bee, I sting when I need to, but it hurts me and I hate doing it, so I'm just keeping clear of danger. :O)

"If I were a shadow, I know I wouldn't like to be half of what I should be."
Mr Otsuka, the old black tomcat in Kafka on the Shore (Haruki Murakami)

Hi IsaoShi, you make me feel less alone - I sense you've gone over this stretch of road yourself, and recognise those potholes in my understanding. Thanks for your insights - they are always most welcome!

There is a Poser group I belong to. The (unwritten, tacit) guiding philosophy of this group is "helping each other helps each of us". It is with this mindset that I come with these questions - annoying as I must seem to Those That Know. I feel if my understanding has gaps, others must be in the same place. And on my blog then, those questions can be addressed.

As to my blog, it's a blow-by-blow. Someone comes along and points out a glaring error, I'll correct the error (with credit given). It doesn't pretend to be an authoritative work on the subject... it's all about sharing.

The thing I love so much about scripting and why I wish more people got into it is: I feel you actually get a much clearer idea - almost like an outline, or dot-point explanation - of what a shader's doing. Even after I've cranked out a fairly elaborate GC shader for some clothing item which incorporates some of the original shader (correcting certain settings), I can go back and remember what it's mean to be doing in the script much easier than looking at a spaghetti-salad of nodes.

Monterey/Mint21.x/Win10 - Blender3.x - PP11.3(cm) - Musescore3.6.2

Wir sind gewohnt, daß die Menschen verhöhnen was sie nicht verstehen
[it is clear that humans have contempt for that which they do not understand]

Metaphor of Chooks

I'm completely lost as to what to do in order to do whatever this topic was instructing me in. Can someone dumb down this gamma correction fix for me?

If not, it doesn't matter. Poser7's math functions are beyond me, as math was and is my worst subject.

Do the impossible, see the invisible

ROW ROW FIGHT THE POWER

Touch the untouchable, break the unbreakable

ROW ROW FIGHT THE POWER

Quote - Next question.

Gamma correction is necessary only for image files used in a shader and only for diffuse or specular channels. [ T / F]

False on many levels. You conflated several questions and asked it wrong. Let me re-assemble the question in various forms, leaving out or adding certain words, and answer each:

Gamma correction is necessary ... for images files used in a shader ?

Incoming images are either linear (such as HDR images) already or gamma corrected which require anti-GC measures to make them linear. In no case would you want to gamma correct them. Did you mean to ask about anti-GC? Images such as JPEG photos should be anti-gamma corrected, to make them linear, if they are not already linear. HDR and EXR images are supposed to be linear already. Some are not. If it looks right, it's not linear, and you need to anti-GC it.

*[Anti] Gamma correction is necessary only for images ... ?

False. Any color parameters chosen on the basis of how they look on the screen (such as from a color picker) must be entered in linear representation, or you risk shifting hues and saturation around. For example, the color sRGB(255, 128, 64) is not the actual linear color value you should use. In order to do proper linear math with that color, you should anti-GC it. Notice I said sRGB to indicate I'm talking about the values you read off from picking or sampling a color on the screen and then examining what RGB values you got. Consider if you used that color with a 50% light. What should the on-screen color end up being, half those values? Nope, because half of those would not be half as luminous.

In general, if the color you like in your sample or color picker is X, then you should be using X ** 2.2 in the script.

By the way, in all your scripts, you keep writing very long things like:

gamma = Add(2.2)
color = ImageMap("blah blah")
gamma_pow = Color_Pow(color, gamma)

I find this incredibly tedious to read, as I have to study many characters to see what you did.

This gets the exact same job done:

ImageMap("blah blah") ** 2.2

Also, the lovely thing about this expression is that if "color" is really just a color, then you don't need any nodes, and matmatic will just do the conversion for you, for example:

IColor(255, 128, 64) ** 2.2 # will result in the linear representation of what 255, 128, 64 looks like on the screen

*[Anti] Gamma correction ... only for diffuse or specular channels.

False. It is also needed for any incoming material that is coming from gamma corrected sources. In particular, reflections coming from other GC shaders on other surfaces are in sRGB color space, not linear color space, and have to be anti-gamma corrected before you use them in calculations.

Quote -
Since bump and displacement don't use colour information, it is not necessary to perform gamma correction on dedicated bump and/or displacement files, [ T / F]

True.

Quote -

or node-based colours and textures.[ T / F]

True, assuming you anti-GC'd any colors that you fed to those nodes from outside. Remember, that includes images and colors you manually enter into parameters.

Renderosity forum reply notifications are wonky. If I read a follow-up in a thread, but I don't myself reply, then notifications no longer happen AT ALL on that thread. So if I seem to be ignoring a question, that's why. (Updated September 23, 2019)

Note: Poser Pro does all the anti-GC for you. Any color parameters you enter into nodes are automatically linearized in poser Pro when you enable GC rendering.

Renderosity forum reply notifications are wonky. If I read a follow-up in a thread, but I don't myself reply, then notifications no longer happen AT ALL on that thread. So if I seem to be ignoring a question, that's why. (Updated September 23, 2019)

Quote - I'm completely lost as to what to do in order to do whatever this topic was instructing me in. Can someone dumb down this gamma correction fix for me?

If not, it doesn't matter. Poser7's math functions are beyond me, as math was and is my worst subject.

Use my shaders. I take care of it. The thing going on here is RobynsVeil wants to write her own somewhat complicated shaders that do more than what I have published so far. So all this math is important and cannot be simplified. She's combining on the order of 10 colors and images in her shaders, to do dynamic makeup and stuff.

Renderosity forum reply notifications are wonky. If I read a follow-up in a thread, but I don't myself reply, then notifications no longer happen AT ALL on that thread. So if I seem to be ignoring a question, that's why. (Updated September 23, 2019)

Here's a demonstration of the problem you get if you do not anti-GC all incoming colors.

I'm trying to make an orange vase (TrekkieGrrrl's freebie).

I put the orange color into the Diffuse_Color. I add the diffuse and specular, then gamma correct.

I get a tremendous shift in hue and saturation. Luminance is right, but the color is all wrong.

Renderosity forum reply notifications are wonky. If I read a follow-up in a thread, but I don't myself reply, then notifications no longer happen AT ALL on that thread. So if I seem to be ignoring a question, that's why. (Updated September 23, 2019)

This is a proper implementation. I anti-GC the orange first. Now I get the correct color, including hue, saturation, and luminance.

Renderosity forum reply notifications are wonky. If I read a follow-up in a thread, but I don't myself reply, then notifications no longer happen AT ALL on that thread. So if I seem to be ignoring a question, that's why. (Updated September 23, 2019)

Imagine that orange was actually from a color map. See the problem? The RGB (255, 128, 64) value we see as orange is only that color when viewed on a monitor. The actual amount of red, green, and blue is wrong from a linear color representation standpoint. As a result, everything gets shifted around when we gamma correct at the end.

There's no difference between using a simple orange color everywhere and using a color map filled with orange. They both need to be dealt with the same way. That orange is not actually 255, 128, 64. The only time that is the right number is to get that p;articular color to show on your screen. That is not the actual numerical value in linear color space.

Renderosity forum reply notifications are wonky. If I read a follow-up in a thread, but I don't myself reply, then notifications no longer happen AT ALL on that thread. So if I seem to be ignoring a question, that's why. (Updated September 23, 2019)

Quote - > Quote - 1 * Color_Map - 0

What value does that give you?

Another question:

Plugging a color into a numerical Math node parameter converts the color to gray scale. The Subtract node Value_1 is what I'm talking about here.

What happens if you plug a color into some other numerical node parameter. Suppose you plug it into Bump or Displacement. What is going to happen?

A related question: If I connected 500 of these Subtract(1 * x, 0) nodes in series, what would change?

Related to that, if I connect no subtract nodes here, what changes?

If you plug a color into the numerical Math node granted if it's a solid color the only thing that will happen is nothing, especially if it's in the displacement or bump node. If that's the effect you're going for, then it's better to leave it off. But if you want to add some "umph" into the existing texture that the creator so kindly forgot to provide the bump or displacement map, you can add a quickie bump or displacement node.
As for the 500 of these nodes in a series, I would imagine the effect to be negligible after the first 2 nodes (I don't know. I am not an expert like you, BB. Half of the information I've received about the mat room came from that lil noggin of yours. The rest from tips and experience. ).

Even the first two do nothing. That was what I was trying to get across. If 500 of them do nothing, why would 1 do something?

Renderosity forum reply notifications are wonky. If I read a follow-up in a thread, but I don't myself reply, then notifications no longer happen AT ALL on that thread. So if I seem to be ignoring a question, that's why. (Updated September 23, 2019)

First off, thank you for being so precise and so clear in your answers, where my questions were - because of my ignorance - nebulous due to (as you put it) conflation... neat word. The information in these last few posts have done more than you would ever believe to bring the process out of the fog. I had to know the why - this cleared it all up! Thank you again, Bill.

As to my incredibly wordy code: I agree... makes writing code almost pointless... just string the bloody nodes together, it's quicker, right?

May I ask you a quick question? Just one more? Please? (sheesh, I'm annoying, even to ME!)

When I do this stuff:
gamma = Add(2.2)
color = ImageMap("blah blah")
gamma_pow = Color_Pow(color, gamma)

I have three nodes that I can dictate .inputscollapsed and .pos to by name:

gamma.inputscollapsed = 1
color.inputscollapsed = 1
gamma_pow.inputscollapsed = 1

and similarly do positioning on the material room floor. However, if I:

ImageMap("blah blah.jpg") ** 2.2

...I get all kinds of nodes I have no idea how to reference so I can tidy things up. Call me pedantic, but I like things working right and tidy too. With emphasis on the former. Is there a way to do so from within a script that you know of?

Monterey/Mint21.x/Win10 - Blender3.x - PP11.3(cm) - Musescore3.6.2

Wir sind gewohnt, daß die Menschen verhöhnen was sie nicht verstehen
[it is clear that humans have contempt for that which they do not understand]

Metaphor of Chooks

When you use infix operators, matmatic will pick a node to implement it, same as if you said it explicitly.

colorWithGC = Color_Pow(ImageMap("blah.jpg"), 2.2)
#or
colorWithGC = ImageMap("blah.jpg") ** 2.2

colorWithGC is a node - it got made the same either way

therefore we can do

colorWithGC.inputscollapsed = 1

Renderosity forum reply notifications are wonky. If I read a follow-up in a thread, but I don't myself reply, then notifications no longer happen AT ALL on that thread. So if I seem to be ignoring a question, that's why. (Updated September 23, 2019)

You could also make a handy function to collapse the inputs on anything:

def collapse(x):
x.inputscollapsed = 1
return x

Having that, you could say:

colorWithGC = collapse(ImageMap("blah.jpg") ** 2.2)

Renderosity forum reply notifications are wonky. If I read a follow-up in a thread, but I don't myself reply, then notifications no longer happen AT ALL on that thread. So if I seem to be ignoring a question, that's why. (Updated September 23, 2019)

Puzzled.

I was quite certain that if I did "to the power of" maths, it would generate additional nodes that I couldn't re-label or reference. However, now they seem to stay in place, except for the ImageMap node, which seems to have a mind of its own.

Here's the whole script: it's not long. I'm converting a dress texture to GC. I carefully recreated the connections that existed before, except now there's anit-gamma / gamma processing code. Also, instead of connecting to Diffuse_Value, I connect to Alt_Diffuse. Those values I have changedA lot of the original shader is questionable, even to my limited understanding. So, ignoring some of the values for the moment (my biggest issue is the s.Reflection_Value = 3):

def makeSurface(region):
# Colour / other Maps
dispBumpMap = ImageMap("VDRflwr_rpd01D.jpg").labelled("Disp-Bump Map")

# !!!!!!!!!!!!!!!!!!! CHANGED
# convert to linear colour space - this node does not obey '.pos =' directives
linearColourMap = ImageMap("VDRflwr_rpd03.jpg").labelled("linear ColourMap") ** 2.2

dressClr = IColor(45, 17, 94) #Purple
venClr03 = IColor(127, 127, 127) #Grey
venClr04 = IColor(177,153, 200)
# For the reflection channels
venClr02 = IColor(205, 198, 255)

if region == "flower":
    reflClr = IColor(0, 0, 255) #Blue
if region == "dress":
    reflClr = IColor(142, 242, 255) #Light Blue

setWeave = Weave(
    Color_1 = WHITE,
    Color_2 = venClr02,
    Base_Color = BLACK * linearColourMap,
    U_Scale = 1,
    V_Scale = 1,
    Height = 3,
    Bias = .3,
    Gain = .5).labelled("Sets Weave")
setRefl = SphereMap(reflClr * setWeave).labelled("Sets Reflection")
setDiff = Diffuse(dressClr * linearColourMap, .7).labelled("Sets Diffuse")

!!! Changed - had labels indicating what these nodes did... now they just say Color_Pow

Convert back to sRGB

gamma = setRefl ** (1 / 2.2)
gamma2 = setDiff ** (1 / 2.2)

# Arrange nodes
gamma.inputsCollapsed = 1
gamma2.inputsCollapsed = 1
linearColourMap.inputsCollapsed = 1

gamma.pos = 250, 50
gamma2.pos = 250, 75
linearColourMap.pos = 250, 100   # doesn't stay there - goes right off the screen

setDiff.pos = 500, 100
setRefl.pos = 500, 200
setWeave.pos = 500, 300

dispBumpMap.pos = 720, 300



# Make the actual surface
s = Surface(1,0,0,0)
s.Highlight_Size = .25
s.Translucence_Color = venClr03 * gamma
s.Reflection_Color = venClr04 * gamma
s.Reflection_Value = 3 * gamma
s.Bump = dispBumpMap * .03
s.Displacement = dispBumpMap * .006
s.Alternate_Diffuse = gamma2
return s

outputs += [
"-Flower", makeSurface("flower"),
"-Dress", makeSurface("dress"),
# "-Borders", makeSurface("borders"),
# "-Ribbon", makeSurface("ribbon"),
]

Just whenever you get to it is fine, Bill... I realize you're an incredibly busy man, and this nonsense must be really frustrating to you. Thanks again for your patience.

Monterey/Mint21.x/Win10 - Blender3.x - PP11.3(cm) - Musescore3.6.2

Wir sind gewohnt, daß die Menschen verhöhnen was sie nicht verstehen
[it is clear that humans have contempt for that which they do not understand]

Metaphor of Chooks

And one could somehow also create a function that would do the same thing with position, incrementing some variable? Kinda like:
nodePos = 10

def nodePosition(x):
x.pos = nodePos + 25
return x

linearColourMap = nodePosition(ImageMap("blah.jpg") ** 2.2)

I'm thinking the value of nodePos would increment with each call of nodePosition? Or am I getting By Reference mixed up with By Value again? In Python, it's always by reference, right?

Monterey/Mint21.x/Win10 - Blender3.x - PP11.3(cm) - Musescore3.6.2

Wir sind gewohnt, daß die Menschen verhöhnen was sie nicht verstehen
[it is clear that humans have contempt for that which they do not understand]

Metaphor of Chooks

Attached Link: LCD and CRT Monitor Calibration Software

give away of the day has a monitor calibration software as todays give away

"This program will help you to calibrate your LCD or CRT displays without any hardware devices for 6500K gamma 2.2. "

check it out

You might as well PAY attention, because you can't afford FREE speech

Carefully re-reading your fine manual - the one that came with Matmatic - which revealed this:

"Arithmetic involving just colors or numbers is entirely performed inside Matmatic. No nodes are generated for these."

Pretty unequivocal. So, I conclude that if I've got some maths nodes I didn't set out to generate, that there's a flaw somewhere in my code. This is distinctly possible. Now, as to creating names for basically maths nodes:

**"... if you're trying to find a particular step, or you want to document the tree for people who are not using Matmatic, you can change the labels on the nodes. Every node has an attribute called label. Set it to anything you want. Another way, more inline during expressions, is to call the node method .labelled(desiredlabel). This sets the label and returns the node, so you can use it in expressions. Example:

R = sqrt((x * x).labelled("X sqrd") + (yy).labelled("y sqrd")).labelled("radius") "*

I'll just shut up now and sort out where I went wrong with my code.

Monterey/Mint21.x/Win10 - Blender3.x - PP11.3(cm) - Musescore3.6.2

Wir sind gewohnt, daß die Menschen verhöhnen was sie nicht verstehen
[it is clear that humans have contempt for that which they do not understand]

Metaphor of Chooks

Hi RV:

I'm sorry I didn't answer your recent questions. Some of the questions are big, like how to automatically lay out nodes in a way that will facilitate parameter jiggling in the material room. I've been thinking about how to add that to matmatic in a standard way that is both convenient and flexible. I don't have a solution yet, and don't have a lot of time. I'm about to go on vacation for a week (leaving Saturday) and I have a lot of paid work to do first.

Regarding math node generation, it's pretty simple. Using any of the math operators, if both operands are known constants at compile time, the math is done at compile time.

For example, suppose a = RED and b = GREEN, then a + b is YELLOW, not a Color_Add(RED, GREEN).

However, when you wrap constants in a Node, such as a = SimpleColor(RED), then a + b is not YELLOW. The assumption here is you wrapped RED in a node because you want that node in the shader so people can change it. Which means we can't conclude the answer is YELLOW - the addition of the two colors must be deferred until render time.

Renderosity forum reply notifications are wonky. If I read a follow-up in a thread, but I don't myself reply, then notifications no longer happen AT ALL on that thread. So if I seem to be ignoring a question, that's why. (Updated September 23, 2019)

Hope you have a great holiday (vacation), Bill!

Just real quick - you said that if I select a colour via the colour-picker, then it needs to be linear colour-spaced (anit-gammaed) before processing, just like any jpg images coming in.
I interpret that as: anything I reference via IColor(255,0,0) is colour-picker stuff (because that's where I'm looking at a colour to select it and typing in those values based on what I see), whereas Color(1,0,0) wouldn't be? Am I on the right track?

And do have a great time! Looking forward to your safe return (and piccies, if you have any... :biggrin: )

Monterey/Mint21.x/Win10 - Blender3.x - PP11.3(cm) - Musescore3.6.2

Wir sind gewohnt, daß die Menschen verhöhnen was sie nicht verstehen
[it is clear that humans have contempt for that which they do not understand]

Metaphor of Chooks

Ummm.

IColor(255, 0, 0) and Color(1, 0, 0) are identical.

The difference is merely a unit change - like Fahrenheit versus Celsius.

0 degrees C is not different from 32 degrees F, just because one number is 0 and the other number is 32.

The reason to anti-GC or not has nothing to do with how you typed it in. It has to do with what you're trying to represent and how you'll use it.

For example, if you're trying to use a color multiplier that decreases green by half, you would NOT want to convert that. That isn't a color that has a specific appearence when you read it off as an RGB value. Rather, it is a tuple that has 3 components, each of which is to be used as a multiplier, so the correct value is Color(1, .5, 1) or IColor(255, 127.5, 255) - it doesn't matter how you say it, it matters how you arrived at it and how you'll use it.

If you arrived at a color by choosing from various values on the basis of how they look on the screen in sRGB color space representation, then you want to convert that to linear (anti-GC) before you use it.

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There are some interesting and surprising ramifications of doing everything linearly.

Consider creating a gradient from pure 100% BLUE to pure 100% RED. What color would be in the middle, and how bright should it be? Intuition tells me that it should be a MAGENTA hue in the middle, but how bright?

Consider this script:

a = Color(0, 0, 1)
b = Color(1, 0, 0)

x = (U - .5) * 1.5 + .5
nonLinearGradient = Blend(a, b, x).labelled("nonLinearGradient")
linearGradient = Blend(a ** 2.2, b ** 2.2, x).labelled("linearGradient") ** (1/2.2)

combination = Blend(linearGradient, nonLinearGradient, .5 <= V)

Surface(0,0,0,0, Alternate_Diffuse = combination)

If you put that on a square, it renders the non-linear gradient on the upper half and the linear gradient on the lower half.

The linear gradient produces a bright magenta, because both of the end colors are bright. The non-linear gradient produces a very dark magenta, and the red and blue each dominate until you're nearly in the middle. The linear gradient is the correct path through the color space from blue to red. The non-linear gradient deviates towards black in the middle of the transition, because those colors with darker values for red and blue do not display with the correct luminance.

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Another example, this time with:

a = ORANGE
b = BLUE

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One more

a = Color(.2, .9, .7)
b = Color(.8, 0, .6)

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More typical is the gradient produced by lighting yielding a diffuse reflection. When the surface faces the light, it is brightest. When it turns away, it is darkest.

a = SKIN
b = BLACK

The upper gradient is what Poser renders with a skin color and you don't do GC. The lower gradient is how the skin renders with GC. This is why a GC shader looks so much better for human skin.

If you force yourself to imagine the lower (linear) gradient is 3D, you can convince yourself you're looking at a cylinder, not a flat surface.

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Straight-forward enough... thanks for the samples. For my makeup, I've chosen colour from the MS colour picker - which looked bright enough on my screen. I will need to convert to linear before I manipulate it with Blenders and Spots and such (and then gamma the result - I call the node "sRGB Out") before I plug it in to PoserSurface.

Thanks for taking the time to explain that, Bill. Have a good vacation.

Monterey/Mint21.x/Win10 - Blender3.x - PP11.3(cm) - Musescore3.6.2

Wir sind gewohnt, daß die Menschen verhöhnen was sie nicht verstehen
[it is clear that humans have contempt for that which they do not understand]

Metaphor of Chooks

Some observations:

I'm doing all these gamma-correct conversions to clothing and hair and so forth, and am having some interesting times with the shaders some people have put together. For one thing - and I see this ALL the time - people are setting PoserSurface.Specular_Value and Diffuse_Value to 1. Both to 1.
Doesn't this violate the conservation of energy law?
I think I know why they do, though. If they did try to do the CoE thing using those channels, the colour in the preview pane would be shockingly dark (because they haven't converted the colours to linear colour space, for one).

Regarding node creation (and how to avoid it)... if I do this:

gcVal = Add(2.2)
clrBlue = IColor(0, 0, 255) ** gcVal

...I get a Colour_Pow node (as well as the Math_Functions(Add) one). If I do:

clrBlue = IColor(0, 0, 255) ** 2.2

...I don't. I now have a linear colour space version of the colour I wanted which I can process. If I want to use it - say - in the Diffuse_Color channel, I would just:

clrBlue = clrBlue ** (1/2.2)

...just before doing:

s = Surface(1, 0, 0 ,0)
s.Diffuse_Color = clrBlue

...and the sRGB version of the colour would display.

Am I getting this?

Monterey/Mint21.x/Win10 - Blender3.x - PP11.3(cm) - Musescore3.6.2

Wir sind gewohnt, daß die Menschen verhöhnen was sie nicht verstehen
[it is clear that humans have contempt for that which they do not understand]

Metaphor of Chooks

I'm trying to catch up on Gamma here... can someone veryfy that I'm understanding this right...
Different monitors are likely calibrated at different Gamma (is it Gamma range)?
I gather most PC monitors, out of the box, are around 2.2 gamma range? (At least when I load Gamma chart in themonitor at work, that's the value I read.

My monitor at home, which is extra bright, reads at Gamma 1.5 (at current settings, which I like). However, before I post something online, for others to view, I should adjust this image so people with your average gamma 2.2 monitors can see it, and it not being dark and muddy looking? Photoshop has gamma adjustment, so I should be able to just tweak the gamma setting... While on my home monitor it will look a bit washed out, it'll look fine on your avearge PC monitor?

In general terms, am I understanding this right? I read parts of the thread, but I'm getting too lost in specific terminology to really follow it. I need it broken down in plain english, so I can start catching up. Thanks :)

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By the way, I'm using this to read/check/adjust gamma on my monitors and images.
http://www.photoscientia.co.uk/Gamma.htm#menu

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Oh boy. So you decide to bring up the complicated scenario, heheh.

Monitors are supposed to be set so that they display sRGB content directly, which is approximately a gamma of 2.2.

Any material that is constructed while staring at the results on such a monitor (such as hand-drawing a texture color map) is encoded with the gamma level of the monitor at the time of construction. I don't mean the data is impacted in some way, I mean that the human making color choices was impacted by the gamma of her monitor. So you need to respect the monitor response curve that the author was using, not you, when dealing with her material as incoming material that requires anti-GC.

Now if you want to design an output for your extra bright gamma 1.5 monitor, then you want your outgoing GC = 1.5, but you STILL need your incoming anti-GC to be 2.2, unless the incoming material was designed while LOOKING AT YOUR MONITOR. If you judged a color combination nice on your monitor, you must assume that the linear value is anti-GC(1.5). If the incoming material was judged nice on somebody else's workstation, then you must assume they were using 2.2.

Renderosity forum reply notifications are wonky. If I read a follow-up in a thread, but I don't myself reply, then notifications no longer happen AT ALL on that thread. So if I seem to be ignoring a question, that's why. (Updated September 23, 2019)

In that linked gamma discussion, the guy suggests adjusting for gamma=1.8 and says supporting stuff that will get you in trouble. Stuff such as:

"A gamma of 1.8 agrees fairly well with the output of most printers. "

Wrong. All printers today, especially photo printers, expect photos/images in sRGB color space, which is much closer to gamma=2.2 than 1.8. The only reason there are printers at all in 1.8 is because graphics work used to be the realm of Mac users and Mac used to be 1.8. Hello - that hasn't been the case for 10 years now - the Internet has changed all that. Mac is now 2.2, and far more people LOOK at images on 2.2 than 1.8. Far more. Like a factor of 10,000 to 1.

"It gives Mac users one less excuse to sneer, and they do enough unwarranted sneering as it is. "

Old news - Mac is now 2.2.

Renderosity forum reply notifications are wonky. If I read a follow-up in a thread, but I don't myself reply, then notifications no longer happen AT ALL on that thread. So if I seem to be ignoring a question, that's why. (Updated September 23, 2019)

He also said this: (underline added by me)

Quote - There are a number of gamma checkers and so-called 'calibration' patterns out there on the web that will give an entirely false reading or setting of your system gamma.
They're all based on the same fallacy: That of using a dithered pattern which is too small to properly represent the correct brightness value(s). (For the technically minded; the problem is caused by the risetime of most monitor hardware not being sufficiently fast to turn from full black to full white in the space of a single pixel, or even two, in some cases.)

Hello dude it is 2009 - nobody uses scanning monitors any more. We all have LCD displays where each pixel is a real independent device and can show any color perfectly regardless of what its neighbors are showing.

Renderosity forum reply notifications are wonky. If I read a follow-up in a thread, but I don't myself reply, then notifications no longer happen AT ALL on that thread. So if I seem to be ignoring a question, that's why. (Updated September 23, 2019)

Quote - Some observations:

I'm doing all these gamma-correct conversions to clothing and hair and so forth, and am having some interesting times with the shaders some people have put together. For one thing - and I see this ALL the time - people are setting PoserSurface.Specular_Value and Diffuse_Value to 1. Both to 1.
Doesn't this violate the conservation of energy law?

Yes although your interpretation of it is not correct either. This is really complicated and I don't have time to explain it. I'll summarize, and hopefully that's enough:

It sounds like DV + SV <= 1 is a good rule, but it doesn't work out. The reason is that the specular value is not the whole story - the angles have to work out as well. Further, if the DV is .8, the SV can still be 1 (100%), but it means the specular effect has stolen the opportunity for the diffuse effect. This means that where the specular is strong, the diffuse is suppressed. I do this in my shader like this:

spec = Specular(whatever)
#or
spec=Blinn(whatever)
#then
diff = Diffuse(diffColor, .8 * (1 - spec))

This is not perfectly accurate physics, but it's closer than anything else you could do with Poser, at least until I think of something better. Look at the VSS shader - it is done this way.

Quote -
Regarding node creation (and how to avoid it)... if I do this:

gcVal = Add(2.2)
clrBlue = IColor(0, 0, 255) ** gcVal

...I get a Colour_Pow node (as well as the Math_Functions(Add) one). If I do:

clrBlue = IColor(0, 0, 255) ** 2.2

...I don't. I now have a linear colour space version of the colour I wanted which I can process. If I want to use it - say - in the Diffuse_Color channel, I would just:

clrBlue = clrBlue ** (1/2.2)

...just before doing:

s = Surface(1, 0, 0 ,0)
s.Diffuse_Color = clrBlue

...and the sRGB version of the colour would display.

Am I getting this?

Yes, but perhaps you don't see the correct reason. You stopped using a variable and that isn't the difference. The difference is 2.2 versus Add(2.2). The value 2.2 is a number, while the value Add(2.2) is a Node that generates that number.

gcVal = 2.2
clrBlue = IColor(0, 0, 255) ** gcVal

is the same as:

clrBlue = iColor(0, 0, 255) ** 2.2

but not the same as:

gcVal = Add(2.2)
clrBlue = iColor(0, 0, 255) ** gcVal

Because you're asking me to clarify the rule here, I thought it necessary to make the distinction. In you example, you changed two things at once, and so it's not clear why there is a difference - either or both changes may have caused the delta. The reason is the value of the operand - doesn't matter how you typed it, either as a constant or a Python variable, if it is a number, it's dealt with at compile time. If it is a node, it's dealt with at shading time.

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RV: You had the CoE stuff correct in your example CoE thread at the Node Cult.

Set up specular node

setSpec = Blinn(1,.4,.65,.4)

Set up the Diffuse node, keep it from exceeding conservation of energy with Specular

setDiff = Diffuse(linearColormap, .**7 * (1 - setSpec)).**labelled("Set Diffuse")

Renderosity forum reply notifications are wonky. If I read a follow-up in a thread, but I don't myself reply, then notifications no longer happen AT ALL on that thread. So if I seem to be ignoring a question, that's why. (Updated September 23, 2019)

Quote - Oh boy. So you decide to bring up the complicated scenario, heheh.

Monitors are supposed to be set so that they display sRGB content directly, which is approximately a gamma of 2.2.

Any material that is constructed while staring at the results on such a monitor (such as hand-drawing a texture color map) is encoded with the gamma level of the monitor at the time of construction. I don't mean the data is impacted in some way, I mean that the human making color choices was impacted by the gamma of her monitor. So you need to respect the monitor response curve that the author was using, not you, when dealing with her material as incoming material that requires anti-GC.

Now if you want to design an output for your extra bright gamma 1.5 monitor, then you want your outgoing GC = 1.5, but you STILL need your incoming anti-GC to be 2.2, unless the incoming material was designed while LOOKING AT YOUR MONITOR. If you judged a color combination nice on your monitor, you must assume that the linear value is anti-GC(1.5). If the incoming material was judged nice on somebody else's workstation, then you must assume they were using 2.2.

Gotcha :)
That sounds a lot like what I've been doing... When I make an image, I make it for a particular 'output' device... It varies from a printer to a printer, and what monitor... So, if I want something to look as intended on the average monitor, I need to make it look a bit washed out on my main monitor (I have an older one here I can always look at)... For the most part, after you've done it enough time, it can be done just visually, sort of winging it.

I was doing a quick little informal poll, as an extension of a thread here: http://forum.daz3d.com/viewtopic.php?p=1778953&flatnum=1 regarding how many people see the image as relatively dark, and whom sees it as acceptable. I was curious, because over time I fot the impression that in Poserdom there may be a larger then usual percentage of people with higher quality, brighter monitors then on the average....

So, I wonder if that info, or an educated guess is of any use to me, whom should I target, your usual 2.2 gamma monitor, or graphics people whom have likely tweaked it (or your graphics hobbyist whom I've seen in the past making thise tweaks to their monitor settings to what just looks good, without being fully aware of wht they're doing exactly.

Of course, if I was doing a regular graphic, for a wide audience website, I'd probably calibrate the image so it looks right at gamma 2.2... or something in between 1.8 and 2.2... actually, probably stick to lighter colored images and color schemes... they tend to be a bit more 'web safe' when it comes to monitor Gamma.

In Rendo Gallery, I posted images that looked good on my bright monitor, with no adjustments, asking people if they look too dark.... and usually more answers are that it's not, rather then it is... But then again, I know that is highly subjective.

Anyway, when I saw you post a reminder about gamma correction, I was scratching my head wondering, what Gamma value do we optimize them for... and was reluctant to ask for a while. I think it's sinking in now, you want people to stick to optimizing for around 2.2.

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Quote - In that linked gamma discussion, the guy suggests adjusting for gamma=1.8 and says supporting stuff that will get you in trouble. Stuff such as:

"A gamma of 1.8 agrees fairly well with the output of most printers. "

Wrong. All printers today, especially photo printers, expect photos/images in sRGB color space, which is much closer to gamma=2.2 than 1.8. The only reason there are printers at all in 1.8 is because graphics work used to be the realm of Mac users and Mac used to be 1.8. Hello - that hasn't been the case for 10 years now - the Internet has changed all that. Mac is now 2.2, and far more people LOOK at images on 2.2 than 1.8. Far more. Like a factor of 10,000 to 1.

"It gives Mac users one less excuse to sneer, and they do enough unwarranted sneering as it is. "

Old news - Mac is now 2.2.

Thanks Bagginsbill :) Good to know Macs have gone away from 1.8
I actually never worried about gamma numbers too much, but have managed to develop a visual sense for 'how it needs to look on my monitor so it pronts well on my photo printer' etc...

Thanks for the info :)

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Thanks, BagginsBill. I have that CoE expression in pretty much any shader solution replacing a shader with both diffuse and specular. Since I do move the connections from those top channels down to Alt _Diffuse and _Spec, I was hoping for a decent idea of how to go about assigning diffuse and specular values, since the usual DV = 1, SV = 1 I'd be replacing wasn't going to be much of a guide.

Just trying to do maths: what exactly sort of value would Blinn(1, .4, .65, .4) yield? IOW, which channel of Blinn would be yielding the value that:

.*7 * (1 - setSpec))
**
would be evaluating? Looking at channels, it's not like we're comparing apples with apples... both have a color channel as the first one, but whilst diffuse has value, what Blinn yields must be some sort of composite of the rest of the channels. According to your node reference, Blinn yields a colour, and since:

"You can mix Colors and numbers in your arithmetic. Whenever you use a Color and a number, Matmatic first promotes the number to a Color (using the one-number rule)"*

what does happen in that expression? Or is it so complex a calculation involving far more than I could ever get my head around that I would simply be best off just accepting that:
.7 * (1 - setSpec)
is a good default Diffuse_Value to set for Diffuse, and to use the Blinn values as outlined above for most specular-type node replacements.

Just to show my line of... um... thinking... lets say that I'm using a Blinn node where:
Blinn.Specular_Color == WHITE (as in: Color(1, 1, 1))
...does it follow that setSpec == 1?
..in which case,
.7 * (1 - 1)
... no, that can't be right. That would have a value of 0. So, Blinn must yield some other number made up of maths done internally. As would Phong or Glossy or any of the other specular nodes.
I'm probably nowhere near understanding this, as this line of thinking must suggest. And I really am trying to break down questions into single units, although I don't do real well at that.

Monterey/Mint21.x/Win10 - Blender3.x - PP11.3(cm) - Musescore3.6.2

Wir sind gewohnt, daß die Menschen verhöhnen was sie nicht verstehen
[it is clear that humans have contempt for that which they do not understand]

Metaphor of Chooks

Just for information.....

I have a 2-year old Intel iMac with OS X 10.4 (Tiger), and I was sure I had seen the gamma figure of 1.8 somewhere in my setup, long before I had any idea what it meant. So I just ran through the OS X 'Display Calibrator Assistant' again, now that I know a bit more about what it's doing.

It indicated that my iMac display does indeed have a NATIVE gamma response of around 2.2. In fact, my results showed just over 2.3, but of course it's quite a subjective process. It might well be 2.2 after a few refills of my Friday evening wineglass.

But my default iMac display profile specifies a TARGET gamma of 1.8. This probably means that most Mac users are still in fact using an output gamma of 1.8, unless (like me) they re-calibrated their displays and are now using a custom calibration profile with gamma 2.2.

In the 'Simple' mode of the OS X Display Calibrator Assistant there are just two options for target gamma (see screenshot). That's pretty clear. The 'Expert' mode, however, has a slider going from 1.0 to through the ceiling, and by way of guidance says "In most cases it's best to use the Mac Standard gamma of 1.8". Not very helpful.

On a Mac with the default Target gamma of 1.8, both sRGB and GC(2.2) images will appear over-corrected in comparison to what the artist intended. (Put simply, if not entirely accurately, too bright).

And images made by the artist using the same Mac will appear under-corrected when viewed on an sRGB PC display. (.. ditto ditto... too dark).

So I think the simple message to Mac OS X users in this community should be... run the OS X Display Calibrator Assistant in Simple mode, and set your Target gamma to 2.2.

ducks and runs for cover

"If I were a shadow, I know I wouldn't like to be half of what I should be."
Mr Otsuka, the old black tomcat in Kafka on the Shore (Haruki Murakami)

Cool. I have corrected the wording on your Mac.

Renderosity forum reply notifications are wonky. If I read a follow-up in a thread, but I don't myself reply, then notifications no longer happen AT ALL on that thread. So if I seem to be ignoring a question, that's why. (Updated September 23, 2019)

hehe - agreed!

(edit) and " interested in seeing images as other artists intended"

"If I were a shadow, I know I wouldn't like to be half of what I should be."
Mr Otsuka, the old black tomcat in Kafka on the Shore (Haruki Murakami)

I think that dialog is so amusing.

What the Mac calls "Standard Gamma" is not a standard at all. It is used by a handful of starving artists out of a stubborn belief that different is better. These people wear black at all times and have pieces of metal sticking through their noses and eyebrows. They wear glasses that make them look Swedish.

Meanwhile the real gamma as used by every digital camera from $10,000 pro gear to the cheapest pocket point-and-shoot, the gamma used by the display of every cell phone, the gamma found on over a billion PC's, the gamma that appears in every single live television production in the universe, that gamma that every television ever made implements, that gamma is the "non-Standard" "Television Gamma". LOL

Seriously, why would you want your image to not be set for correct display on over 10 billion devices. Why would you choose to have it look right on just a few hundred thousand? (I know there are more Mac's than that, but most are no longer running gamma 1.8)

Renderosity forum reply notifications are wonky. If I read a follow-up in a thread, but I don't myself reply, then notifications no longer happen AT ALL on that thread. So if I seem to be ignoring a question, that's why. (Updated September 23, 2019)

At least in Simple setup mode they had the sense to call it "traditional" rather than "standard".

In your final parentheses you seem to be implying that at some time during the last two years (after I bought my Mac) OS X started shipping with a default display profile specifying a target gamma of 2.2, instead of the 1.8 that mine had out of the box.

I wouldn't bet on it, but I rather suspect that they are still shipping with 1.8. I'm going away to check...

"If I were a shadow, I know I wouldn't like to be half of what I should be."
Mr Otsuka, the old black tomcat in Kafka on the Shore (Haruki Murakami)

From what I can determine, the default display profile is going to change to gamma 2.2 with the shipping of OS X 10.6 Snow Leopard.

So all you Rendo Mac users out there... switch your display profile to gamma 2.2. You know it makes sense, or the men in black wouldn't be doing it!

"If I were a shadow, I know I wouldn't like to be half of what I should be."
Mr Otsuka, the old black tomcat in Kafka on the Shore (Haruki Murakami)

I am using a Toshiba laptop running a NVDIA GEforce Go 7300. I brought up it's control pannel and it says that my gamma is set at 1.00. If I move the gamma slider to around 2.20 (I can't imput the exact number just move the slider and the closest I can get is 2.25), then the screen is blown out too bright and washed out. So I put it back to 1.00.

"A lonely climber walks a tightrope to where dreams are born and never die!" - Billy Thorpe, song: Edge of Madness, album: East of Eden's Gate

Weapons of choice:

Poser Pro 2012, SR2, Paintshop Pro 8

Quote - I am using a Toshiba laptop running a NVDIA GEforce Go 7300. I brought up it's control pannel and it says that my gamma is set at 1.00. If I move the gamma slider to around 2.20 (I can't imput the exact number just move the slider and the closest I can get is 2.25), then the screen is blown out too bright and washed out. So I put it back to 1.00.

And thus the confusion rises, unabated. Not your fault, but NVidia.

The gamma control they are showing you is how much correction you want to put onto your system gamma.

The system gamma is the total gamma built into your system - which includes operating system GUI software, graphics driver software, graphics driver hardware, your monitor hardware settings, and the monitor pixels themselves.

Monitor's actually have a physical gamma of 2.5. The system gamma brings the remaining gamma to 2.2, which is the standard. But you can force it to lower. The gamma you're looking at is your NVidia driver gamma correction. You can adjust that and alter your system gamma. For example if you set your NVidia driver gamma to 1.4 then your system gamma will become 2.2 / 1.4 = 1.57, which means your monitor would start to behave like ConnieKat8' monitor.

Renderosity forum reply notifications are wonky. If I read a follow-up in a thread, but I don't myself reply, then notifications no longer happen AT ALL on that thread. So if I seem to be ignoring a question, that's why. (Updated September 23, 2019)

What, if anything should I adjust? Because when I try to follow your advise and gamma correct my Poser render to 2.20, then the resulting render is blown out too bright. The most I gamma correct my renders is 1.00.

"A lonely climber walks a tightrope to where dreams are born and never die!" - Billy Thorpe, song: Edge of Madness, album: East of Eden's Gate

Weapons of choice:

Poser Pro 2012, SR2, Paintshop Pro 8

1.0 stands for no gamma correction. So if the most you correct is 1 = no correction, you don't correct. :) And I know you GC your renders because you're using VSS right, like your avatar? VSS has GC 2.2 built in by default. You don't need to do anything but use it and you are gamma correcting by 2.2, which is why it looks good on your monitor and my monitor.

You should not adjust anything unless you believe you work doesn't look good. I see it as excellent - so I think you're all set.

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Let's be clear:

We keep making these two phrases "my gamma is" versus "my gamma correction is" - these are two different things.

Your monitor gamma is 2.2. You NVidia gamma correction is 1.0. That means you need/want a 2.2 correction in the render.

If you were to change your NVidia driver gamma correction to 2.2, nothing the rest of the world publishes would look right to you. Just leave it alone. Gamma correction in the driver is only to bring your monitor gamma back to 2.2, not to make the monitor gamma 1.0. You do NOT want your monitor gamma at 1.0, you want it at 2.2. If it looks like 2.2, then you should leave hardware gamma correction turned off - i.e. leave the NVidia setting at 1.0.

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Thank you, I was beginning to get very frustrated because from what I read it looked like I was going about my rendering process all wrong. Yes, I use VSS now almost exclusively on my figures. I had bought and used the Realskin system by face_off. It's good and gives good render results. However it is light dependant. I have to run the script every time I change my light set up, which I might do several times before I get what I want. VSS only needs to be run once, unless I completely switch texture maps. Thank you so much for clarifying this for me! I will feel less frustrated now as I follow the VSS discussion thread.

"A lonely climber walks a tightrope to where dreams are born and never die!" - Billy Thorpe, song: Edge of Madness, album: East of Eden's Gate

Weapons of choice:

Poser Pro 2012, SR2, Paintshop Pro 8

Just so you know, you can run, for each texture, run VSS once and never run it again, even if you switch textures.

When you have a texture set that has been VSS'd and you're happy with it, save the figure's materials as a material collection. Then in the future, you just load that collection again. You never have to use VSS again with that texture.

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Okay, I 've heard of people saving material collections, but I haven't figured out how to do that. If you've a minutes, could you explain that?

"A lonely climber walks a tightrope to where dreams are born and never die!" - Billy Thorpe, song: Edge of Madness, album: East of Eden's Gate

Weapons of choice:

Poser Pro 2012, SR2, Paintshop Pro 8

It's simple. With the figure selected and any material from it in the material room, click the + button in the library.

The dialog pops up to ask for the Set Name. Before saving, change the radio choice from "Single Material" to "Material Collection", then save. All the materials of the figure will be combined into one item in your library.

In the future, select a figure, open material folder, navigate to that collection and double click it. All materials of the figure will be restored.

Save as many of these as you like with different settings.

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Duh! figuratively slapping forehead Thanks BB!

"A lonely climber walks a tightrope to where dreams are born and never die!" - Billy Thorpe, song: Edge of Madness, album: East of Eden's Gate

Weapons of choice:

Poser Pro 2012, SR2, Paintshop Pro 8

Hi all, juste a little stupid question, now i have migrated to poserpro, when i load a texture do i need to to load it with the gamma render setup or with a specified gamma value ?

Thx

Génération mobiles Le Forum / Le Site

As I understand it, the gamma-correction shader is not necessary for Poser Pro users. You simply enable GC and Poser Pro does the process internally.
This thread is addressed to Poser users who do not have that feature in their version of Poser: Poser 5, Poser 6 and Poser 7.

Monterey/Mint21.x/Win10 - Blender3.x - PP11.3(cm) - Musescore3.6.2

Wir sind gewohnt, daß die Menschen verhöhnen was sie nicht verstehen
[it is clear that humans have contempt for that which they do not understand]

Metaphor of Chooks

Quote - Hi all, juste a little stupid question, now i have migrated to poserpro, when i load a texture do i need to to load it with the gamma render setup or with a specified gamma value ?

Thx

Whether you use render Gamma Correction built into Poser Pro or material Gamma Correction as I've been distributing, you have Gamma Correction in either. The important thing is not to have double GC by running GC in both.

Poser Pro's built-in GC will have the advantage of fixing up nearly every material you have that was not designed with GC in mind. However, it will a couple of small disadvantages as well.

* It will anti-GC incoming material such as images, even if those images are data not colors we look at. For example, transparency maps and displacement maps are linear data already. You must instruct Poser not to anti-GC these data sources. However, you don't need to do it for every occurence - just once per source file. It will remember your choices even after starting a new scene. And there is a Python script to help with that, disabling GC on all transmaps and displacement maps in your scene.

To avoid doubling the GC, you'll have to go into any materials from me (Bagginsbill) and set the GC value to 1.0 because everything I distribute now is a GC material. This includes all VSS shaders. As time goes by and everybody moves onto versions of Poser with built-in GC, I'll stop distributing GC materials.

I suggest you use the Poser Pro built-in GC at 2.2. I do it all the time now and find it very convenient.

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Thx for the answer !

Génération mobiles Le Forum / Le Site

Personally, in today's economic times, I don't think people are going to spend the requisite US$100 (which for me in Oz equates to more like AUD$160... far too dear!) to upgrade to Poser Pro for only that reason. Unless SM - or whoever markets Poser in the future - applies some really aggressive marketing scheme to upgrade to Poser 8, I don't see myself upgrading: can't afford it.

So, this solution you've offered, Bill, is one that will continue to be valid and important for thousands of Poser artists for some time to come.

Monterey/Mint21.x/Win10 - Blender3.x - PP11.3(cm) - Musescore3.6.2

Wir sind gewohnt, daß die Menschen verhöhnen was sie nicht verstehen
[it is clear that humans have contempt for that which they do not understand]

Metaphor of Chooks

bump.

start using gamma correction. if you have poser pro you have it in render settings. if you dont have poser pro use GC in the material room.

here is a mini tutorial
www.renderosity.com/mod/forumpro/showthread.php

I've written a quick-and-dirty "How-I-Do-It"... would someone that knows please check for accuracy?

tightbytes.com/wordpress/

The best way to learn is to attempt to teach.

Monterey/Mint21.x/Win10 - Blender3.x - PP11.3(cm) - Musescore3.6.2

Wir sind gewohnt, daß die Menschen verhöhnen was sie nicht verstehen
[it is clear that humans have contempt for that which they do not understand]

Metaphor of Chooks

under scripts/partners/shaderworks/postwork manager we can apply GC to the image. but i noticed that its not correct.

this is BB's GC shader

this from postwork manager

why is it wrong? did they do a mistake?

The setting may depend on the monitor display setting which is 1. Essentially 1 is equal to 2.2! Open your video card display program for your calibrated monitor and notice the Gc setting.

@hborre
I'm confused, if it had to do with his monitor why would his images look different?

@iceboy
By your third image it looks like you GC'd your BB GC image, or am I missing something?

Unfortunately, the newer version of DAZ Studio and Poser's Post Manager take their Gc settings from the Video Card programs. To test this, activate your VidCard program and slide your Gc setting from 1 to 2.2 and observe the results. The monitor image will become increasingly brighter, not darker. Repeat the Gc changes within each 3D app and you will get the same. Basically, changing the Gc in this manner is not the same as other ways of correction. I did come across an article offering a more technical explanation which I will need to find again.

Quote - why is it wrong? did they do a mistake?

Strange ... What is the better ? Using a GC shader, using postwork or setting the gamma of the screen to 2.2 and render always with gamma 1 ?

Now we have HSV tone, too many confusion i think !

Génération mobiles Le Forum / Le Site

I believe that the Postwork Manager is exactly that. It applies postwork settings to a render before you export it. I don't think it actually works during the render process. I think it is like exporting the render, and loading the file into another program to adjust brighteness, contrast, GC, etc..

lmk

Probably edited for spelling, grammer, punctuation, or typos.

The red became pink because the incoming material is not anti-gamma corrected before applying the final gamma correction. If you were to anti-GC everything first, it would work fine.

Post-work GC does not work correctly by itself. Things become desaturated, and hues can shift. Shader GC as I do it works correctly, but has the problem that it isn't compatible with IDL. When IDL is used, the colors coming from shaders must be linear, not sRGB.

However, my HSV GC postwork behaves more like HSV ETM, which means there is less requirement to anti-GC incoming material. But I'm too busy to post it right now.

Renderosity forum reply notifications are wonky. If I read a follow-up in a thread, but I don't myself reply, then notifications no longer happen AT ALL on that thread. So if I seem to be ignoring a question, that's why. (Updated September 23, 2019)

i think you already posted teh HV GC postwork right? we load the render in the background shader.

Yes. You can also put that type of shader on a square (the "Artistic Lens") and render it directly.

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Is gamma correcting for print a different science?

I convert P7 renders to grayscale with PS7.
When I receive proof copies, the gs images can come out pretty terrible.

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That depends on what the printer is expecting. But generally printers expect things in sRGB color space, same as your screen, same as your digital camera produces. In other words, if a photo doesn't print to your satisfaction, then a GC'd render in sRGB space will not print well either. If a photo does print well, then a GC'd render should print well.

Converting a color image to grayscale is another topic with its own complications. There are many ways to do the conversion. Two are most common. The first is to pick the brightest value amongst R, G, and B as the grayscale luminance. The other is to calculated a weighted sum of R, G, and B. The latter is how black-and-white TV worked. The factors in B&W TV are:

.3 * R + .59 * G + .11 * B

I'm not sure which techniques PS7 implements.

Here's a nice little page on the topic with respect to the program "the GIMP":

http://gimp-savvy.com/BOOK/index.html?node54.html

Renderosity forum reply notifications are wonky. If I read a follow-up in a thread, but I don't myself reply, then notifications no longer happen AT ALL on that thread. So if I seem to be ignoring a question, that's why. (Updated September 23, 2019)

Forum: Poser - OFFICIAL

Subject: Monthly reminder - you need to gamma correct your renders

colorWithGC is a node - it got made the same either way

therefore we can do

!!! Changed - had labels indicating what these nodes did... now they just say Color_Pow

Convert back to sRGB

Set up specular node

Set up the Diffuse node, keep it from exceeding conservation of energy with Specular