Huge issue: SSS + fake shadows messes up phong angle
Posted: Sat Dec 19, 2020 7:18 am
Hi, so this is a huge issue that simply doesnt have an answer, and I've spent months looking for an answer. I always ended up compromising but I have a project that requires extreme realism and I want to figure out what is going on.
So, as was already discussed here, SSS with fake shadows on removes phong angle from model. That results in a heavily faceted look.
Here are the "solutions" that don't really work on the internet:
1. Increase Subdivision Surface - Doesn't resolve faceting, just makes polys look smaller and still faceted. Also, makes scene unreasonably heavy.
2. Increase Ray-Epsilon - This works, but it causes other huge problems. One is that the color of the SSS becomes extremely saturated and dark, and there's no real way to fix it as much as I try to make the color and scatter lighter. Also, It causes ugly artifacts in the small details where objects overlap or are placed close to each other due to the higher ray-epsilon.
3. "Smooth" option on the Common tab in the material doesnt fix it. Messing with the phong tag doesn't fix it.
The only thing that actually works, is unticking Fake Shadows. But then, the SSS requires high scatter depth.
Here's the examples
First I tried to work with the exported DAZ model I have, this has Ray Epsilon of 0.00001 (Needed a lower Ray Epsilon to solve something else in this scene):
After trying endless of different combinations and fixes, I tried to work with a model known to have perfect topology and textures to see if I still get it
Ray Epsilon 0.0001:
Ray Epsilon 0.001 (look at the artifacts where the lips and eyelids touch):
And here's how it looks with no Fake Shadows on ray epsilon 0.0001:
As you can see, the fake shadows cause this issue. Is this a known and unfixable Octane in C4D issue? Because I've seen people get good results without faceting using this technique in Octane on other programs or not using Octane.
Here's how I made the material - Albedo is black and Transmission is on 100.
Any tips of other tricks? Is this simply not the way to achieve highly realistic skin in Octane for C4D?
Should I just use a different approach to SSS that might look less realistic?
Thanks!
So, as was already discussed here, SSS with fake shadows on removes phong angle from model. That results in a heavily faceted look.
Here are the "solutions" that don't really work on the internet:
1. Increase Subdivision Surface - Doesn't resolve faceting, just makes polys look smaller and still faceted. Also, makes scene unreasonably heavy.
2. Increase Ray-Epsilon - This works, but it causes other huge problems. One is that the color of the SSS becomes extremely saturated and dark, and there's no real way to fix it as much as I try to make the color and scatter lighter. Also, It causes ugly artifacts in the small details where objects overlap or are placed close to each other due to the higher ray-epsilon.
3. "Smooth" option on the Common tab in the material doesnt fix it. Messing with the phong tag doesn't fix it.
The only thing that actually works, is unticking Fake Shadows. But then, the SSS requires high scatter depth.
Here's the examples
First I tried to work with the exported DAZ model I have, this has Ray Epsilon of 0.00001 (Needed a lower Ray Epsilon to solve something else in this scene):
Ray Epsilon 0.0001:
Here's how I made the material - Albedo is black and Transmission is on 100.
Should I just use a different approach to SSS that might look less realistic?
Thanks!
