5.5: pathtracer, MRQ, subsurface scattering, noise

Development Rendering
1

Hello,

To rule out one thing:
Yes I know about Max Path intensity in the PostProcessVolume pathtracer settings.
When I set it from default 24 to 10, the result has way less noise, now it is at 3, but the result is not better
I use subsurface scattering like in the meercat demo and I use the unreal engine eye from… (5.2?).

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It looks nice on the fur and the background plants.
But the subsurface scattering materials (eye and nose) have so much red noise in them.
When turning on denoiser, on the other hand, it completly blurres my normal map on the skin and often, smudges the fur aswell.
Light: HDRIBackdrop, with a 8k EXR file, directional light. - i followed tutorials for this.
It seems to be stronger in shadows, or, mostly in shadow areas.

a) Do you have ideas how to get rid of the subsurface noise?
b) I did not find a good tutorial on the denoiser, I would realy like to use it, but the effect is way too strong. Both, for standard and for NFOR denoiser.

Just noticed, green noise in the iris. HM

2

Hi!
Have you tried increasing the “Samples Per Pixel” setting on your lights?
I’ve just had the same issue with subsurface causing noise in a few areas, and increasing said samples on the lights in my scene seemingly solved the issue for me.
(Don’t go too wild on the numbers though because it can have an impact on performance. 5-10 spp, per light, worked in my case without increasing render times much.)

I know it’s been a while since your original post, but I hope this helps! o/

3

Thank you for the reply!
I actually don’t remember how i solved this problem, but I did. Far less reds left. I think I deactivated one of those lights.
I will try your ideas next time. Although I thought, the MRQ already maxes out the Samples Per Pixel!? via game settings override or something.