V6 Belle Eyes
I have been doing some renders with V6 using the default Belle materials. I have noticed some issues with the eyes. For example, look at the eyes in the render below of V6 and G2 Female that I posted in the V6/G2 render thread. V6 is in the white and black dress. G2 is in the red dress. The iris of V6 eyes looks washed out. It is hard to tell what color her eyes are.
I have been looking at the surface settings trying to figure out what is causing this. The diffusion textures for the iris are not washed out like this. I have been fiddling with the eye surface settings and I think I have found 2 things that are causing this.
1) The new G2/V6 surfaces have an EyeReflection surface, in addition to the Cornea, Iris, Pupil, Sclera. The G2 skin surfaces have nothing set in this, but the V6 surface has the opacity at 15% with a texture and reflection at 10% with a texture in the reflection color. The texture used in both is a black and white street scene with buildings, cars and people. I suppose this is suppose to be reflected in her eyes somehow. The V6 Belle skin also comes with 3 eye reflection presets, but these presets do not change the EyeFeflection surface at all. These presets seen to change the opacity in the Cornea surface with a texture. There also is no preset I can find to remove these reflection presets once you apply them. The settings in the EyeReflection surface seem weird.
2) I think the SSS setting in the Iris are too strong and washing out the Iris. In general the default SSS settings for V6 is way too high in my opinion. I have been using the SSS 25 preset. I'm not sure that preset lowers the SSS in the eyes though.
The second image shows close up renders the the default V6 eyes with the SSS 25 preset, then with the opacity and reflection turned off in the EyeReflection surface, then with both the EyeReflection and Iris SSS turned off. The last render seems to get the eyes back to something normal looking.
Is this a problem with the material or is this the way it was intended to be?
Comments
I've noticed it too. I've taken to using darker eyes on the character, since the eyes render kinda pale that sometimes only her pupils show making her look poor-especially from a distance.
What type of lighting are you using... is it the uberlighting? It looks rather flat so that could throw off the materials.
The closeup renders of the eyes were done using lighting like described in this post:
http://www.daz3d.com/forums/discussion/24312/#359710
All the lighting is all from UberAreaLight planes. I am not using UberEnviroment at all.
This lighting does produce fairly uniform lighting without obvious shadows, but there are still subtle shadows to the give it a 3D look.
The first image of V6 and G2 in a bar, the main light is from an UberAreaSphere. There are a lot of point lights too. That render is also a Gamma 2.2 corrected render. The eye closeups are Gamma 1.0 renders.
I tested it and the V6 Belle Skin SSS 25 preset only changes the SSS strength in the skin surfaces. The Irises surface stays at 50% strength.
I've been doing some more renders, and I get the impression this problem is worse in Gamma 2.2 renders. The iris in V6 eyes seems to almost disappear. This is especially true of the green eyes.
Maybe a dumb question, but why use SSS on eyeballs at all? They are wet shiny surface, surely most light just bounces off/reflects, rather than act the way ears and nostrils etc do, no?
SSS is on the irises, I think. In real life those are a bit shiny too, but there's definitely some scattering going on. They're velvety almost. The whole eyeball will scatter light in a way that could use SSS as well, aside from the clear cornea. And there is indeed a shininess to the whole thing, which is why I was so delighted to see a separate full eye surface return in addition to the cornea/sclera.
The problem I see here is to a great extent the natural SSS in the irises is already been captured in the diffusion texture for the irises. Applying more SSS on top of what is already in the texture is causing a loss of detail in the irises. Also the SSS strength is 50% in the irises, which seems way too strong to me. The SSS 25 preset does not change the SSS in the irises, only in the skin surfaces.
The problem I see here is to a great extent the natural SSS in the irises is already been captured in the diffusion texture for the irises. Applying more SSS on top of what is already in the texture is causing a loss of detail in the irises. Also the SSS strength is 50% in the irises, which seems way too strong to me. The SSS 25 preset does not change the SSS in the irises, only in the skin surfaces.
That's almost certainly true, though I can't make any specific comments myself as I haven't loaded up the character.
High SSS tends to wash out textures in general. Applying the diffuse or bump to the SSS channel can help counteract it somewhat.
or perhaps multiply the texture map with a darker version of the eye color in the diffuse? Not sure if you can do that in studio though, I haven't even dove into the shaders much in DS.
You can with the layered image editor. Click the down arrow next to the diffuse, choose LIE, add a new layer, load the eye texture into it, set it to multiply, and adjust the strength. You could also just change the diffuse color on the iris to something darker than white.
I wonder if having a sharper image with more tonal range in the SSS would help too.
Edit: the forum seems to have reversed the order of my images, so I reworded the post.
I did some more test renders using Gamma 2.2 lighting. The first image shows the V6 head with the default eyes and the Genesis 2 eyes. This was cut out of a larger scene render I'm working on. At this scale with the default V6 eyes, the irises have almost disappeared. If you look very closely they are faintly there, but the eyes simply don't look right. With the Genesis 2 eyes you can clearly see the irises at this scale.
The second image shows a comparison of the default V6 Belle green eyes, with the eyes when the EyeReflection surface is disabled and when SSS is turned off in the irises surface. It is slightly better. The lower eyes are the Genesis 2 green eyes applied to V6. The Genesis 2 green eyes are obviously much darker. You can see this if you look at the textures.