VRay Environment Fog flicker hard to get rid of

[freedomfries]

When using a VRay rect light to cast rays into a Environment fog node, I have been dealing with lots of flickering, that doesn't seem to get solved by increasing subdivs in the fog node, or in the light, or increasing sampling in render settings. After many attempts, deleting the fog node creating a new one appears to fix the issue. Is there any known issue with rectangle lights and the Vray Environment Fog node? I have not seen much abotu this while searching the forums. My set up is very simple. My render layer has only one light used to cast rays into the fog. I haven't had problems like this before.

[vlado]

I’m not sure what may be wrong. Can you share your setup or send it to me at vlado@chaosgroup.com?

Best regards,
Vlado

[freedomfries]

Thanks for responding Vlado. Unfortunately, I finished the job this week and have left the studio, so I cannot provide you with scene info. What I can tell you is how I worked around it. The VRay rec light was causing the issues, so I replaced it with a Maya area light and enabled Vray light attributes on it. The look was slightly different, but the flickering in animation was gone immediately, without changing any other settings. This issue came up in three different Maya scenes, for different shots.

[vlado]

Interesting, ok - thanks a lot for the information.

Best regards,
Vlado

[Pallaris]

Having the same flickering issue when casting rays with a VRay rect light into an Environment fog volume. Seems to be happening when the camera is 'looking into' the volume or more or less parallel with it.

Using a Maya Area light is a workaround.

(VRay Next update 1.1)