It was a time all people create somes shaders, who works fine i guess, without any question, and brutaly it's question of gamma correction !

Why, Who ??? Since poser 5 -> poser 7 nobody need gamma correction, this one can be done under psp or ps with layers ...

Its a "mode" ?

there are two threads i think from bagginsbill. i think it is explained there.

your monitor doesnt show you the real deal .you need GC to see what really happens in the render.

cameras have GC,pro 3D software,photoshop,.....

Ok !

I dont know if using GC in the shaders is a good thing ... If your monitor is corectly calibrated you dont need adding more additional correction in your render i think !

For exemple i'm on a "candle dinner" ...

All two pics have the same lights. Look at the table, for an intimate dinner i prefer without and yet my screen is correctly calibrated ( i think with adobe gamma ).

It's a "mode"?  My understanding of this question is: "Is it really necessary? Is it here to stay?"

I am sure the answers are: "Yes, and yes". Why?

There is no doubt that many Poser users want and expect to see good images coming straight out of Poser. Many amateur/hobby/casual users are disappointed and discouraged by their inability to get anything approaching realistic lighting and shading in their renders.

They can take a normal snapshot with their digital camera, upload it to their computer (as a JPG image) and display it on their screen, and it looks fine. But they set up a simple scene in Poser and display the render on their computer screen, and it looks horrible. Why? Well, at least partly because their digital camera automatically corrects the image so that it will look right on a computer screen; but Poser does not.

They are confused by the explanation that it is their own fault because they are not Gamma Correcting their renders. They don't understand why it's necessary, they don't have the image editing software required to post-correct images, or they just don't know how to do it.

Many people, many different reasons, but one consequence: many images with no GC being displayed on computer screens that require images with GC.

So the latest release of Poser (Poser Pro) has a built-in Gamma Correction capability. This must be a good thing for many users, and I believe it should (and will) be a standard feature in future mainstream Poser releases, not only in the "Pro" version.

Oh... regarding your images. If you use gamma correction, you often need to adjust the overall lighting intensity. Many people increase the intensity of their lights to try to compensate for too-deep shadow areas in a non-GC'd image. A direct comparison between the same scene setup with and without GC is not entirely appropriate.

But I have to agree with you that your non-GC image is better in this particular case, mainly because of the table and chairs!

Izi

I want well, but if all the renders need to be the same as Poser Pro cause it have GC, where do we go ?

When i use 3ds or rarely bryce or imagine, i dont make a stamp on the GC !!! My work is based only on my light and my shaders ( event is there nothing !) and never on the " how can be view this picture" ... On en finirait plus !!!

Shadering is a good choice, but the better is the friendly bad friend ...

Quote - They can take a normal snapshot with their digital camera, upload it to their computer (as a JPG image) and display it on their screen, and it looks fine.

Thats not really true. I remeber times as the photo hobbiests have published their gratefully and workfully done pictures in foto magazines. But since the digital revolution has invented telephones to make photographic pictures, the internet is overcrowded with rubbish images ... maybe (not really) technical rather well done but with senceless content.
But this is not the real point, see below ...

Quote - But they set up a simple scene in Poser and display the render on their computer screen, and it looks horrible. Why? Well, at least partly because their digital camera automatically corrects the image so that it will look right on a computer screen; but Poser does not.

This is the true difference. Out there in real world the nature is doing the lighting, the sun, the atmoshere, the clouds, and, and, and. You are seeing the result and if it's interesting for you, your camera is used to make a picture of that. It only depends on the technics of the camera how good the image will be. At that point GC and other things are touched.

If you work with poser the user has to do all that what's done normally by nature. So he has to ligthen the scene for his taste and, assumed his monitor is well calibrated, he should render finally if he's mostly satisfied with the artificial look and feel.

Quote - Many people increase the intensity of their lights to try to compensate for too-deep shadow areas in a non-GC'd image.

With look to every photoshop workshop, tutorial or also the gamma curve, GC doesn't influence darkest or brightest areas a lot. It's mostly working in the midrange. Can be seen in the demo pictures. It influences the desktop but not the candle flame nor any of the shadows at the wall or under the desk.

So with a look to all the smaller or bigger flaws poser is having with light and shadow, e.g. lights instead of shadow seen behind a dense wall, it's no solution to do any only technical aspect with single shaders. If it's of no artistic value it's a loss of ressource ... though a interesting scientific aspect.

As far as for example GC is not a general function of the program it's better done with programs developed for that, e.g. photoshop, psp, gimp, ... if neccessary.

Just my two cent ...

en.wikipedia.org/wiki/Gamma_correction
www.renderosity.com/mod/forumpro/showthread.php
www.renderosity.com/mod/forumpro/showthread.php

Quote - I want well, but if all the renders need to be the same as Poser Pro cause it have GC, where do we go ?

When i use 3ds or rarely bryce or imagine, i dont make a stamp on the GC !!! My work is based only on my light and my shaders ( event is there nothing !) and never on the " how can be view this picture" ... On en finirait plus !!!

Shadering is a good choice, but the better is the friendly bad friend ...

You don't have to GC your renders just because you are using Poser Pro. You can turn the GC off completely if you want to. But the issue here is nothing to do with artistic interpretation, it is purely technical... and it is this:-

The display on a standard sRGB computer screen of a Poser scene rendered in linear colour space, using input image maps that have not been un-gamma-corrected, and an output image that has not been gamma-corrected, is a very specific and avoidable misinterpretation of the physics of light and shade within the scene. This is not an opinion, it is a simple technical fact.

GC in postwork -- even if the user knows how to do it and has the software to do it -- does not correct the misinterpretation that has already been introduced by the linear rendering of non-linear texture maps.

Now, many people who ignore GC completely do produce wonderful works of art that I can only aspire to, so I am not at all critical of anyone's preferred methods. As I said, this is nothing to do with producing good works of art.

But I believe it is far better (especially for those who do not know about these things) to be provided with software that gives them, out of the box, the best possible interpretation of reality, at a particular price point. The purpose of putting GC into Poser is simply to move somewhat closer to that ideal.

This is a very complex subject, but I hope this helps.

Few people seem to realize WHY they add so much light to the scene, or why it is so hard to keep the lighting looking good if you move anything.

The reason is that adding lights, particularly IBL, decreases the perceived produced by looking at a linear render on your sRGB computer screen.

Here is an example. I have here a few props. Those on the left are not gamma corrected. Those on the right are gamma corrected. The non-GC props look pretty good, because I've used a 60% white IBL and a 40% infinite light. That's a LOT of light. A real-life scene would NEVER have that much light coming from all directions. But to keep the non-GC objects from looking strange, Poser users add lots of lights and set them really high.

The GC props look over-lit, and they are!

Now the non-GC looks terrible. It is too dark, and the reflected light decreases too rapidly with the changing angle of incidence.

The GC props look right.

If you look closely at the cube, the side face of the GC cube is the same color as the front face of the non-GC cube. The non-GC cube is unrealistically dark, especially on the side, but also on the front. It is not correct to say that mid tones are affected more than darker areas. In fact, if we measure the perceived error (not actual error, but our perception of it), the darker the are, the worse the problem is.

I have annotated the graph heavily, but let me summarize.

The dashed lines show how much light is reflected from a single 100% infinite light, or spotlight, or pointlight, based on the angle of incidence. Angle of incidence is the angle formed between the vector pointing at the light, and the vector pointing straight out from the surface, i.e. the surface normal.

When the angle is 0, maximum reflection occurs. Here in this diagram, the value 1.0 in the Y axis indicates the amount of diffuse reflection, as a proportion of the maximum possible. Of course this curve moves up or down depending on the intensity of the light and the color of the surface.

When the angle is 90 degrees, no reflection occurs.

The solid lines show the same reflectance but assuming a 60% white IBL and a 40% infinite light.

The blue lines are the actual correct calculated linear value. The red lines are how bright those values appear on a computer monitor which has been properly calibrated to the sRGB color space. sRGB is the standard for all (S)creens. S.

The black lines show the difference between the correct value and the perceived value. The little dots highlight all these corresponding values for a single angle of incidence.

Notice that the solid black line (actual illumination difference with extra lighting, such as IBL) is lower than the dash black line (actual illumination difference with just a single directional light) for most angles. The dashed line peaks around 60 degrees, while the solid line keeps going up all the way to 90 degrees. What this means is that when you add more light, you make the brightest parts look less wrong. But you also make the darkest parts look MORE wrong.

If you look at the blue and red dots, you'll see that at 25 degrees, the directional lighting is wrong by 11%, while the IBL lighting is only wrong by 4.5%. That is cutting the perceived error in half, and that's why you like to add more light. It makes most of a human face, which is within 25 degrees of your main light, look closer to normal or real. A perceived error of 4.5% is certainly tolerable, and if you light up your figure with lots of lights at all different angles around it, then it will look pretty good! But what if you're trying to use more realistic and directional lighting?

Things get ugly at other angles.

I did many experiments, and learned to add more lights just like the rest of you, but things NEVER looked realistc. They simply looked less bad. That's because even after adding a lot more light, the error is still 14% at 45 degrees. A mistake in shading of 14% is very noticeable. This is the sort of thing people put up with all the time, and it is precisely why my shaders are so popular. I work hard not just to get the realism error under 14%, but usually I get it under 3%.

This is also why some people, even though they use my shaders, get not so good results. They over light the scene, and don't know why it doesn't look real. This is why. You must use GC in the shaders, or the render, or in postwork. Obviously I prefer in the renderer, but I'll do it in the shader if I have to. I never do postwork to fix shader and lighting problems.

At this point, even the extra light doesn't do you much good. The perceived error is 23% and just goes up from there. But that's still much better than the 56% error produced by the direcitonal light!!!

So - GC has little influence on your perception of brightly lit things. But everything from midtones to darks is bad to worse.

I guarantee you, that if you un-learn your bad habits of over-lighting your scene, and instead use GC, you will find that everything looks more real, and more consistent, and it is easier to make artistically motivated changes in your lighting.

However, just because you use GC shaders, does not mean you will achieve realism. You will simply achieve an absence of total suckage. To get realism, you must do much much more with textures, bumps, colors, patterns, and how these respond to light. But at least if you get the lighting correct, then you can stop endlessly adjusting lights trying to solve the problem the wrong way.

I typed too fast here - did not check what I wrote.

In the first post I left out a key word, bolded here:

The reason is that adding lights, particularly IBL, decreases the perceived error produced by looking at a linear render on your sRGB computer screen.

But it is decreasing your realism. In your render, the front of the figure looks ok, but all the surfaces facing away from the light, such as the sides of her arms are way too dark in proportion to how much her front is lit.

Oh, one more thing. To properly get the effect of a flame as a light source, you need to take into account the inverse-square falloff. Light intensity decreases with the square of the difference.

Poser doesn't implement this, but by putting a shader on a light, you can actually get it to do that properly.

In your render, the falloff of the light along the wall was due to the angle change, not the distance. If you gamma correct you can suddenly see that a point light or spot light is illuminating the surface too evenly. This was compensated for by the way your monitor darkened some parts of the walls, creating the illusion that you had the inverse square falloff going. But many things are much more realistic if you actually do all the physics correctly.

people didnt use GC so many years that some here now think that this is something ''fancy''.

like you said for years we used to much light to make good renders. the renders that looked good that looked ''realistic'' were using trick shaders and a lot of lights. nothing wrong with that. but those people spend hours to try doing something that you can do with GC in 2 minutes.

GC is nothing new and GC is nothing fancy. GC is something obvious and old. its just poser didnt have it.

I think i begin to understand THX ALL !!!

In fact, adding GC while the render help to adding correctly the lights and theyr intensity, if ive understand what you said !

You got it Anthanasius. The big advantage to this technique is it is the proper way to see your render, so you can actually tell what you are doing.

For example, without GC, you could place a fill light to help a certain part of the figure's with dark colors and you have to turn it up pretty high. But then you notice that this fill light is illuminating the figure's skin too much. How can a light simulatneously be the right amount and too much? The answer is you need to GC, not to fiddle with lights.

There is a thread right now asking about how to make a light shine on some things but not shine on others, even though they are both in the path of the light. Guess why this person is doing this? You got it, they are not gamma correcting. Which means the perceived error on some items in the scene is higher than others, and no single setting of the light is perfect, so they want to turn on and off which things are lit. Basically, instead of using GC on this scene, the person is wanting to set up several lights FOR EACH OBJECT IN THE SCENE.

Ridiculous.