I try to record today many time the step by step but my poser crashed.. later i fixed my mashine so I am late sorry!! will post tomorrow in the morning everything..

and the radiance effect? just captured the light from the scene .. with a mirror ball but virtual , tomorrow more info about!
this is good but only to use in one scene and everytime you do new scene you have to make it again.. but well the effect is great and render much more faster as extra lights..
and the effect is good b/c the light come not from all direction as you see on the box only exactly from right and left.. you can use all colors what ever produce light or have a bright colors ...

It's looking more & more like We're able to produce the look that other systems need heavy duty math & render time to produce (Global radiosity, Photon mapping, etc...all trying to produce the natural irradience & reflection that light brings to all surfaces).

I know what I will be doing in the morning :-)

Glad your machine is back up...Internet was down all day today here (but thankfully I was not working out of home office, so I didn't miss too much,) Couldn't add more P7 work here today... .oh well.  At least I snapped a few stills for my HDRI so a little Poser productive heh

Out of curiosity, why does the cardinal direction matter, considering the photo may be taken from any random angle, and still come up with a good light source?  (Just askin' ;) )

The direction matter b/c if you make a real scene with a sunset you don't want to have the sunset on the east side right? or if you create a angular map you don't want to have the sun light on the wrong place, would be not natural, beside the studio light what is everything allowed..
If i take a picture for the background I have to know what is direction of the sun so I can set up good the specular and sun light too.. it is very important, mixing the directions will not match good the HDR IBL together.. pple forget that what they see in the mirror ball is what we don't see in the scene at all, and it is mirrored picture that why the confusion about the directions, I made this mistake 2 years ago, but until today I made a very good research about and many many tests .. and one more time again, standing with the face to the south, the west would be always on the right side..and east on the left... that why the model in the factory state scenes always have the face to the south..

Ok, so some rules of thumb are you need to have the sunlight coming from the direction of the sun on the HDR probe light.  Are there any good rules of thumb regarding the actual placing of the HDRI probe light?  Do you necessarily need more than 2 lights in a rig?

NO HDR Light Probe pluged into poser light is moving only if you move the scene using the camera, you can't change the direction of HDR IBL by moving the light .. the rest of the lights you use can fly around as you wish, you can use one HDR IBL but that is only the light that come from the sky and the elements around the model, this is the light that are reflected on earth from everything around you, for a great effect as shadows, specular or a direct sun light you need to use only one more light , you can set down the diffuse to black if you want only the specular effect .
you dont need more that 2 lights to make it looks real..  HDR IBL bright up very much the model surfaces, setting the Diffuse color to R: 127 G: 127 B: 127 will change the surface and it will looks more natural.. don't worry it will not make the textures looks darker.. if you have good and real HDR light probe , the Intensity is fine on 1,0 so the contrast on 1,0 should works perfect..

The east/west directions are reversed.
When you take the picture of the mirror ball, you are the on the outside.
When you make the picture into a environment (viewed from the inside), the directions are flipped.

EDIT - forgot to say I had to rotate the small sphere 180 degrees; else you would be looking at the opposite side also.

I don't know still what you mean.. he don't said much beside images
you can't use a background picture and put an a sphere his test this on a picture of a light probe that was taken against the south (sun ) the photographer that made the light probe for poser7 mapped the hdr map little not usual and reverse the directions...
you should use a sphere map shader node and not a texture map for the sphere to get it working correct..

The problem is if you mistake the direction merging the photos for the ladi/longi the light probe will be total wrong so the light

I didn't make the .exr, Paul Debevec did; but I understand about the directions and how to assemble the images (but my photography is not very good yet). It was confusing at first; but learned the right way.
Anyway, I almost always use them as spherical environments and don't normally attach any geometry to them. When I do that (sphere environments) the directions of the original image files are the correct ones, of course. So if the images have the right direction, the environment will too. Then the skylight can just use the environment, and all is well.
I'm not rendering w/ Poser but am always interested in HDR, so this is a very interesting thread to me.

I undersand, but if somebody make a hdr light probe from many pictures merge together should know it and how it works so the light will show correct in the poser scene for example..this is not big problem using a mirror ball b/c you will get always everything right, but if you try to make it by creating a lad/long sphere map and convert it to a Light probe the attention of the directions are very important..
if you make many pictures in place of using a mirror ball start taking pictures always from the north side the way to east-south-west-and back to north this way by mering you will get correct sphere map that you can convert to light probe and use with poser.. this way the north would be always visible as background in the scene b/s we wanna get the light most on the front of the model and not only behind ( in some scenes it is fine but that is not the standard of the direction and your background would never match the light )

:lol:

Thank you, that is a beautiful pic!! the apples looks like direct from the tree, not cleaned yet hahaha
and you lough ? matematic , geography and cartography that what run poser.. we want reality right? so let's do it as it is in real... lol where you should go if you don't know the right direction? I remember my geography classes, my teacher was so strong and frustrated and without a  mercy... I was thinking for what I need that all, I wanna be painter.. now i can use it as well! God bless him ! lol

****"Train a child in the way he should go, and when he is old he will not turn from it."
[Proverbs 22:6]

"I believe that children are our future...Teach them well & let them lead the way...Show them all the beauty they posess inside"
["The Greatest Love of All" ~ Michael Masser]

We don't realize just how much of what we learn (or don't learn) is used in our everyday lives as adults. I am thankful for all of my science & "geek" knowledge growing up, as well as my art & musical studies. Chaucher, Plato, King James, Xmen & Popular Mechanics lol... what a combination! But all that & everything else helped shaped who I am & my drive to open eyes to what they have before them.
We often overlook the greatest gifts right under our noses, & want what we don't have, instead of using what we have to get what we want (or need) ****

I think I should withdrawal from the thread, because it must be completely different and would have no use for Poser HDR rendering.
Anyway, you are making very nice HDRs; hope you keep making them.

Alex, you have right! but "If you don't have what you like, you have to like what you have! " ***[Catharina Harders..The Real Life].. lol

dvlenk6
***and back to the track, no I don't think you are on a wrong place here, poser use the same way of HDR as other programs, with only one thing that the HDR IBL Light in poser don't need the spherical environment, the light with the HDRI do that all, and for the spherical environment and reflections we use the spherical mapping shader node so everything the same but without the BALL ( DOM)  however I made already a products with 360 degree for panoramic rendering using a DOM for the sky maps...
They should do that in Poser and allow the users to load the spherical Angular HDR maps also as360 degree  backgrounds that would be much more fun ... as we have in Vue
the link you provided is great, very cool previews of the panoramic renders

Please feel free to stick around dvlenk6. Everyones input contributes something.  We are all learning & can teach something even if we don't realize it

More info on making angular map/lightprobe images

http://www.myanimator.com/research/hdri_ibi/notes/index.html

http://www.myanimator.com/research/hdri_ibi/tutorial/index.html

The principals are the same, regardless of the rendering engine.

Hi everybody!

Cath,

I made all those pictures to demonstrate the issues with using a photograph on an environment sphere. I was trying to avoid words, as they are imprecise. However, I seem to have failed, so now I will try words, and more pictures later if necessary.

You have disagreed with me on several things that are extremely important in this context. I hope I can convince you to change your mind on them so that we can all get back to the interesting use of these images. For example, I wrote about using a virtual chrome ball in Poser to make your own IBL images that are consistent with your scene. I wrote about this more than a year ago. This is a very good idea, and I'm pleased that you came up with it as well. However, there are some refinements to the technique that I'd like to talk about. But first we have to clear up these coordinate mapping issues. 

Before I get into them, I want to point out that we do agree that the angular map image we use on the IBL must be consistent with the panoramic image we use on the environment sphere. What we do not agree on is how to accomplish that.

First you have stated that I got east and west mixed up. Yet my renders show a compass as well as an image mapped on a semi-transparent sphere that are 100% consistent from all viewpoints. You have repeatedly stated that I must use a 2 to 1 ratio image in order to avoid this problem. 

My last slide contradicts that. I showed you three different image maps and the corresponding render. The first is 2 to 1 as you insist must be used. The second is 1 to 1. The third is 1 to 2. Yet all three renders are identical. The ratio of the image width to height does not matter, as long as the information remains the same. Regardless of how you resize the image, if the aspect ratio of the FINAL PROJECTION ON THE SPHERE is the same, then the results are the same. I agree that if you place a circle of identical aspect ratio in those three image maps, you will get different shapes and only the 2 to 1 will produce a circle. But if you squash the circle so it is consistent with the aspect ratio of all the other objects in the image, it will end up looking the same on the sphere.

Let me put it another way. I can take any panoramic image made by anybody, and use photoshop to resize it so that it is no longer 2 to 1. This will have zero impact on the position of the things in the image. Of course the resulting change in resolution will have an impact on the quality of the render, but this has nothing to do with the position of each part of the image.

I had hoped my renders made that unambiguously clear. If you still believe the aspect ratio of the image matters, then I don't know what else to say.

Second, you said that there is nothing wrong with the UV map of the Poser Hi-res sphere. There most certainly is something wrong with it. I demonstrated in the renders that some of the image is missing. In particular, viewed from the west (looking east) you will see that one edge of the image is completely missing, and that the remainder of the image has been stretched. In all your demonstration images, you failed to show us the sphere from all directions.

You did not see this because every image you attached to your sphere in your demonstrations had no features in the U direction. You had stripes in the V direction, but no visible change in the U direction. If you only use horizontal stripes, you cannot tell if some is missing or not. An image like that proves nothing.

Please try this experiment. Pick any 360 panoramic image or diagram. Use the map of the world if you like. Apply it to your sphere. Now render it from different angles, so you eventually see every part of the sphere. You will see that part of the image is missing on the west side.

You can also demonstrate the U coordinate problem using the Tile node. Start with a new sphere. Attach a Tile node - the node that makes red and blue squares. Set the Tile_Width to .05, so that the aspect ratio of the tiles matches the aspect ratio of the UV map. Leave all the other values at their defaults. This will give you roughly accurate square shapes along the equator. With your camera facing north in the default starting direction, render the sphere. Looks good. Now orbit your camera so you are facing east, looking at the west side of the sphere. Render. You will now see that the tiles are messed up.

Look closely at how I corrected this. You must use a U_Scale of .83333 (25 / 30) to correct the problem. This is because the UV mapping of the vertices on the sphere is wrong, and as a result, 1/6th of any mapped image never appears. In the U direction, they do not go from 0 to 1 as they should.

Now orbit your camera so you are looking straight down on the sphere. Render. the north pole is completely messed up!!! I don't have a workaround for this.

Looking down on the sphere, count the tiles around a circle. There should be 20 identical tiles. It is closer to 16 and 2/3rds.

Now change the U_Scale to .041667. This is .05 times .83333. Render from above again. You will now see 20 identical tiles around a circle, as you should. But the north pole is still wrong. So is the south pole.

You may find it interesting that the Poser Torus is also messed up in a very similar way. Try various tile sizes on the torus.

Now that you know where to look for the problem, put a real 360 degree panoramic image on your sphere. Render it so you can look at the west side. You will see that part of the picture is missing, and your left and right edges form a seam artifact.

Finally, you have shown us images mapped on the environment sphere in your demonstrations. Not once have you shown what the sphere looks like FROM THE INSIDE. It is fine to show the external view of a sphere when attaching a map of the world. Ignoring or correcting the UV mapping problems, this will look mostly correct.

As I'm sure you know, when you look at the BACK of a polygon, whatever image is attached will be reversed. Just so, when you are inside the sphere, ALL the polygons are reversed. Any words appearing in your image will be backwards. 

When we attach a photograph to a sphere and look at it from the inside, the photo will be reversed. This is why I negate the sign on my U_Scale. This flips the photo back around so that any words that appear in the photo are shown correctly, just as the camera saw them.

Similarly, because of this reversal, EAST and WEST are swapped. You have shown us images with your markings in the order (from left to right) North, West, South, East. But that is NOT how the compass points lay out on a panoramic photograph. Starting from the North, as you turn 90 degrees to the right, you encounter East. So wherever north is in your image, East is 1/4 of the width of the image TO THE RIGHT. Facing East, a 1/4 turn to the right leads to South. So too on the image, 1/4 to the right is South. Similarly from there next is West, and back to North. So the compass points on a panoramic photograph, left to right, are North, East, South, West as I have done, not North, West, South, East as you have done.

I understand your confusion. Looking from the outside, the words show up in the right places. But it is not correct to look at the sphere from the outside. You must look at it from the inside. From the inside, you must reverse your image, in order to have the words come out right, instead of have them read backward. Therefore, East and West must be swapped.

Finally, when you take into account the .83333 adjustment for the U coordinate scaling, the actual orientation of the image is wrong. South is no longer south. That is why I used a U_Offset in my final demonstration.

So, to sum it all up. Take your panoramic image JUST AS IT IS. Attach it to your environment sphere. Set the U_Scale and U_Offset of the Image_Map as I showed in my slides. You will now have the image correctly projected on the sphere when viewed from the inside. 

I would like to address the IBL (angular map) that goes with this later. FIrst I'll wait to see if I've convinced you of the above or not. We cannot accurately discuss the IBL mapping to go with this panoramic image until we agree on how to handle the panoramic image.

Just to strengthen the understanding of the UV issue, I saved the Poser Hi-res sphere as an obj file. Then I filtered it to find the UV coordinates for the equator (where V = .5). Here are the 36 UV texture values for the 36 points around the equator.

vt 0.142536 0.5
vt 0.166258 0.5
vt 0.189971 0.5
vt 0.213677 0.5
vt 0.237374 0.5
vt 0.261064 0.5
vt 0.284748 0.5
vt 0.308427 0.5
vt 0.332103 0.5
vt 0.355776 0.5
vt 0.379448 0.5
vt 0.403121 0.5
vt 0.426797 0.5
vt 0.450476 0.5
vt 0.47416 0.5
vt 0.49785 0.5
vt 0.521547 0.5
vt 0.545253 0.5
vt 0.568966 0.5
vt 0.592688 0.5
vt 0.616419 0.5
vt 0.640157 0.5
vt 0.663904 0.5
vt 0.687656 0.5
vt 0.711415 0.5
vt 0.735178 0.5
vt 0.758944 0.5
vt 0.782712 0.5
vt 0.806479 0.5
vt 0.830245 0.5
vt 0.854008 0.5
vt 0.877767 0.5
vt 0.90152 0.5
vt 0.925266 0.5
vt 0.949005 0.5
vt 0.972735 0.5

Notice that there is no U = 0 or U = 1 as there should be. The smallest U is .142536 and the largest U is .972735. So the first 14.2536% of the image is never shown, and the last 2.7265% of the image is never shown.

Taking the difference, we see the the U span is .830199 units wide. I used .83333 after much visual experimentation, but now that I've done the math, the correct U_Scale would be -.830199. I'll have to do some experiments to find the correct U_Offset to go with that.

On the left, U_Scale = -1. On the right, U_Scale = -.830199.

Here is a render combining the compass props, the grid map, and the HDRVFX pond image. The point of view was chosen to be able to closely examine the artifact correction on the west side.

I will agree with you regarding the ball, I never saw it b-c the missed parts was always behind the scene NORTH and that was what I missed , on the UV maps including the top and bottom ,
the aspect ratio matter if you are going to convert the maps to Light probe.. but for the textures it don´t matter ..

i will write more in a sec..

P.S my dear, i wrote above that the photographer flipped the north side to the south while merging the images, the light probe is not working correct with the standart direction of poser scene..

I'm so glad you were able to verify the UV mapping problem.

Now what about this North->East->South->West issue? Are we in agreement yet? You must flip the image and look at it from the inside of the sphere, before you judge.

Here is a closeup of a very large (6K pixels wide) panoramic image if New York, mapped onto a sphere and viewed from the inside. I used the U_Scale = -.830199. You can clearly see the word "Verizon" on the Verizon building, and that is the Brooklyn bridge to the right. These positions and orientations are correct and match reality. If you do not flip the U_Scale, everything is backward.

Light Probe that light up the scene in Poser is based on the Latitude/ Longitude sphere map that is very important to show exactly where the scene will be lighted up.. the ground, the sky or the left or right sides.. the red would be for the right hand for us in real world also for the models in the poser scene mean the west, the yellow for the left side..etc... so simple is that 

Cath I understand the light probe and I agree with that diagram. I'm not talking about light probes yet. Why do you keep talking about them.

I'm talking about how to use a 360 panoramic image on a Hi-res sphere so that it works as a visible environment around your scene.

Please take the pond image and mark it with North West South East as you have done. Attach this modified image to a Poser sphere. Render from inside with low focal length so we can see the relationship of South to West, West to North, North to East and East to South.

Also, the words must be legible so we can see that they are not backward.

Look at my images. North->Red is Right->East, and so on. How are those wrong? They are not wrong. But if you render North->West->South->East it will be wrong. If you use North->West->South->East, the words are backward or they are the wrong words. Show me your environment sphere rendered from the inside. You still have not done that. We'll get to the light corresponding light probes afterward.

Ok now is fine, but one more thing, I am right now remapping the sphere to get the thing correct, it is important that the faces are not flipped by the mapping , if you do that then I will agree with your theory but only b-c the sphere map was mapped wrong , let me finish the mapping first so we can both use the new sphere with correct UV´s to make the test and then we can agree or not... I am well curious about as well.. give me a five moments..pls

P.S

Limitation of Sphere Mapping

Although sphere mapping is generally convincing, it is not generally correct. Most of the artifacts come from the fact that the sphere map is generated at a single point and then applied over a large number of points. Objects with interreflections cannot be handled correctly. If reflected objects are close to the reflective object, their reflections should appear differently when viewed from different points on the reflector. Using sphere maps, this will not happen. Sphere mapping results are only correct if we assume that all the reflective objects are infinitely far from the reflective object.

Fixing the eye point along the vector (0, 0, 1) also leads to incorrect results. The same normal in eyespace will always map to the same location in the sphere map. A normal which points directly at the eyepoint maps to the center of the sphere map. A normal which points directly away from the user maps to the circle around the sphere map. Two important advantages of this simplification are that it significantly reduces the cost of computing r and that it ensures that the parts of the sphere map which have the best filtering are mapped to the primitives which face the user. In general, primitives which face the user will cover large areas in screen space and will be the focus of the user's attention.

Interpolation of the texture coordinates also leads to artifacts. Texture coordinates are computed at the vertices and linearly interpolated across the polygon. Unfortunately, the sphere map is not in a linear space, so this interpolation is not correct. Additionally, the linear interpolation will not take into account the fact that the points at the edge of the circle all map to the same location. Coordinates may be interpolated within the circle of the sphere map when they should be interpolated across the boundary.

Cath - you are absolutely correct about the sphere mapping problems. That is why i do not want to use that. I want to use an environment sphere around the whole scene. Then I can use real reflection with no problems.

That is the point of this exercise - how to use a real environment sphere, instead of the Sphere_Map node. It would be great if we had a properly UV mapped sphere to do that with.

But please please do your renders from inside the sphere. Because to use an environment map, you must be inside it, and that changes everything.

WOW ...  I think that thread develops to one of the most important.  Diving into the deep of lighting secrets...  and we are not at the end ;-)  ...   Thank you Cath & bagginbill & ...  for your explanations till this point !!!!  Feels like I'm back at university ... lol!

I see these both as great useful tips. It is always good to have different oppinions on ideas as long as the end result is something an artist is satisfied with and can use.