Optix Volumetric denoising issue

Hello,

I am hoping to get some tips for this volumetric Render problem I have noticed multiple times. In the following pictures you can see my scene and the Render settings. I marked on one of the images the most problematic areas. On the one hand there is this suttle white outline and on the other hand there are denoising artifacts like red “light splatter”. I have tried even higher sample counts than 1024, but it does not improve. I have noticed this issue in other scenes with volumetrics and optix, has anyone ideas for a fix?

The render:

Marked example areas:

Zoom:
test6 zoom

Render settings:

If you have further questions about my settings feel free to ask.

Have you tried denoising it in the compositor as well as optix, or even instead of it?

Thanks for your request. I tried it out, but the results are not really different.

that’s a shame, if I ever render volumes in cycles like this for atmospheric depth etc, I will usually render it onto a different pass(volume pass) as it saves rendertime, but I have never gotten this issue while doing that either.

Are you using the intel denoiser?

No, I use optix because it fits my nvidia rtx graphics card. I have tried out other denoisers, the artifact pattern changes a bit but the problem stays.