Issues with Light exclussion and SSS

[pavelhuerta]

Hello,

I have been having trouble rendering using SSS in Volumetric Scattering mode. In my project I have to light some layers of foam in an ambient way, but to improve the detail level of the fabric surfaces I make use of the inclusion of direct light from two Corona Lights exclusively for the fabric or top of the bed. The problem is that when I activate the lights by excluding everything except the fabric, vertical lines appear on all the materials that have SSS activated. The problem gets worse when I use Deadline Jigsaw, because even though I do a pre-calculation of UHD Cache, the cuts of each render region are noticeable.

I hope I have been clear about this problem and that it can be solved as soon as possible, since currently the only viable solution is to render the top cloth separately and in composition join both results.

Complete Render using SSS and Light Inclussion of the top fabric:


Jigsaw Render using SSS and Light Inclussion of the top fabric:


Jigsaw Render using SSS and turning off the Lights and Inclussion of the top fabric:


Kind regards...

[pavelhuerta]

I forget to mention that the problem is present in the Corona Renderer 5 as well in the new Corona Renderer 6.

Regards...

[maru]

Sorry for the delay.

If possible, please send this scene to us as it may be hard for us to reproduce the exact same lighting conditions:
https://corona-renderer.com/upload

Other than that, I can suggest the following:
- Use path tracing as both the primary and the secondary GI solver. UHD Cache should not help much in this scenario anyway.
- Subdivide the foam geometry. It is possible that you are getting an instance of this issue: https://coronarenderer.freshdesk.com/support/solutions/articles/12000012390

I will now look into this and see if I am able to reproduce similar problems.

[maru]

So far I was able to reproduce results which are a bit odd, but I am not sure if it's the same thing as the original report. I do not know whether "SSS" or "volumetric scattering" mode should be used here, as both are mentioned in the description.
I would need to at least see the material setup. A scene would be even better.

[pavelhuerta]

So far I was able to reproduce results which are a bit odd, but I am not sure if it's the same thing as the original report. I do not know whether "SSS" or "volumetric scattering" mode should be used here, as both are mentioned in the description.
I would need to at least see the material setup. A scene would be even better.

Hi Maru,

So sorry for the super late reply on this. I have uploaded the files through dropbox uploader. Let me know if you have it!

Kind regards...

[pavelhuerta]

So far I was able to reproduce results which are a bit odd, but I am not sure if it's the same thing as the original report. I do not know whether "SSS" or "volumetric scattering" mode should be used here, as both are mentioned in the description.
I would need to at least see the material setup. A scene would be even better.

Any chance to get this solved? Right now the only solution is to render using Path Tracing for primary and secondary GI solvers, but I think it's taking long render times.

Kind regards...

[maru]

Sorry for the delay.
It looks like disabling the "Adaptive light solver" option at the top of the Performance tab immediately fixes this issue. It looks like a bug. I will report it to the devs right away.

(Report ID=CRMAX-144)