Some problems with Fog in scenes with v-ray lights

V-Ray V-Ray for 3ds Max General
1

Hi
We’re doing a underwater animation. We use Environment fog to give the effect of being under water. But there seems to be a couple of problems with fog and v-ray light.

1. problem (see orange text in attached image)
In the animation we get flickering in shadow areas. Have tested with Irradience/Lightcatch and Bruteforce rendering with the same result. The problem disappeared when we did a test with fog turned off.It actually looks very similar to the flickering you got in the old days with irradiencemap without the Prepass/Render animation setup.

Any ideas on a workaround or is it a bug?? We use V-Ray 1.5014 on Max9

2. problem (see green text in attached image)
With fog in the scene invisible v-ray lights shows like a weak transparent shadow. Turning off the fog makes it invisible.

Thanks from Christoffer

fogproblem05.jpg
fogproblem05.jpg512×576 43.3 KB

2

Solved the problem! By setting the Near fog to 0% and moving the Near target beyond the v-ray lights, the flickering disappeared. Seems like the fog can not be in physical contact with the v-ray lights or the objects its lighting up… bug??