Chaos Corona Forum

Chaos Corona for Cinema 4D => [C4D] Bug Reporting => Topic started by: LucasW on 2022-11-05, 21:50:13

Title: c4d 2023 + SSS weird lines
Post by: LucasW on 2022-11-05, 21:50:13
Hi,

I just rendered something with SSS and noticed weird lines appearing.
It seems to be related to the SSS shader, since when I turn it off, it disappears.

Using c4d 2023.001 with Corona 9
Title: Re: c4d 2023 + SSS weird lines
Post by: Beanzvision on 2022-11-07, 08:50:42
Maybe this is some kind of faceting? It's a bit hard to tell without seeing the file. Perhaps, this might help?
https://support.chaos.com/hc/en-us/articles/4528506491025-How-to-get-rid-of-SSS-faceting-with-Corona-Renderer-in-Cinema-4D
Title: Re: c4d 2023 + SSS weird lines
Post by: LucasW on 2022-11-07, 19:11:15
That is what I thought, but the mesh density is already pretty high and it does not seem to follow the topology in terms of edges.
I tried applying a subdiv, but you can still see it. It is also very noticeable during sampling as seen in the 2nd screenshot.
The location also changes with a different camera angle.

I uploaded my scene with only one model in it.
Title: Re: c4d 2023 + SSS weird lines
Post by: Beanzvision on 2022-11-08, 07:13:40
I uploaded my scene with only one model in it.

Okay great. May I ask where you uploaded it to?
Title: Re: c4d 2023 + SSS weird lines
Post by: maru on 2022-11-08, 13:57:14
Does it also happen if you disable the NVIDIA denoiser?
Here is how: https://support.chaos.com/hc/en-us/articles/4528328869649
Title: Re: c4d 2023 + SSS weird lines
Post by: LucasW on 2022-11-08, 18:52:53
Oh wow, I forgot to paste the url.
https://drive.google.com/file/d/1ONhRxmfPazMdeTeKV5SzFcyjOV8QLFjP/view?usp=share_link

Yes, thou, it is less pronounced but basically the same as if you would gather more samples on the nvidia denoiser
Title: Re: c4d 2023 + SSS weird lines
Post by: Beanzvision on 2022-11-09, 13:07:51
Hi there, thanks for the link. I am finding artifacts with your file even without any denoising also. May I ask where the mesh came from? Was it download or sculpted by yourself? I ''tried'' the following to eliminate the artifacts:

1. Deleted the phong tag and replaced it with a new one.
2. Went into points mode, selected all points and used the ''optimized'' command.
3. Enabled the Subdivision Surface modifier
4. Changed denoising mode to ''Corona high quality''
5. Set a noise limit of 4 and let render.

(https://forum.corona-renderer.com/index.php?action=dlattach;topic=38332.0;attach=174146;image)

I hope that helps.
Title: Re: c4d 2023 + SSS weird lines
Post by: LucasW on 2022-11-11, 10:20:04
I sculpted the model in zBrush. Last steps before export where dynamesh, clay polish and decimation master since the original mesh is close to 4m polys and then exported it as obj.
Hm, I guess it must be the topology related, I suspect the clay polish. I will try with the original mesh and see what that does.

Thanks
Title: Re: c4d 2023 + SSS weird lines
Post by: Beanzvision on 2022-11-11, 14:13:59
Okay, thanks for the update. Please feel free to keep us posted here as it may help others also :)