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Problem this week

Light problem

After I fixed the normalmap the lighting didn’t match the same way it did before. So it’s back to light tweaking.

I found a HDR pic with similar lighting, and with a little editing in photoshop I made an image based lighting that I could use as a reference. I won’t use final gather in the final render because I think it gives to little control when I want to edit the light.



I used to render with gamma 0.454, because of the gamma difference in maya and nuke. But I after a rendering today when I had fixed some lights I still thought that the gamma was some what off. And decided to change back to gamma 1 and instead sett the default output profile to linear sRGB. The difference between this two are extremely small, but in the end one was better than the other.



Because I used Misss Fast Skin Shader there weren’t any passes where I could render out the subsurface scattering layer’s. So I had to create my own passes with write to color buffer. Then it was the problem with the shadow passes because this particular shader doesn’t support shadow passes, the solution to this what that I connected the skin shader to a mia x material passes. This shader didn’t have a specular slider but a gloss slider, so I had to make yet another WriteToColorBuffer. The result was a nice and all was well. But when I rendered out the passes this happened to the direct irradiance. And after some testing I found out that the gloss map was to blame. Where there was no gloss/spec on the map (mainly the part where there was twigs and bark) the direct irradiance was completely black. So when I added the overall layer the result was that the bark was almost completely black.

To this problem I made an easy fix, I made the map gray to white instead of black to white. This fixed the black holes in the direct irradiance, then I used a colorCorrect in nuke to amp up the gamma on the gloss/spec map to it’s original contrast. And used the overall layer where I had the bark moss and twigs to cut out the parts of the glossmap that I wanted to have zero spec. It’s an EasyFix and I would like to know how to fix the problem in maya, but for now this fix will do.



This is what it looks like right now, there’s some problem with the bark on the legs. They look very blue and I think it has something to do with the rest of the skinmaps lack of color on that specific area. Will fix that later today.

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