Hello,
got this issue with the lights flickering all over the place when a cube with a volume scattering material is involved. I tried high samples and all, but I cant get rid of those annoying things…
Has anybody an idea how that comes?
Or how I can get rid of those?
Here are two examples:
It appears to be a flicker caused by the lights.
If you think it’s a problem caused by fog, shouldn’t we separate the urban scene from the fog and synthesize it after rendering?
VFX scenes use a method of synthesizing for control of various elements.
thank you for the feedback! It is a cycles scene, rendered all in one. And no, the flickering is not a problem when taking out the “mistcube”… As well there are lights in other sequences which arent visable at all what is also kind of strange in those “big” scenes.
Just watched the video you provided, which uses animated alphas for atmosphere… I am sure there is no talk about the “synthezising” which you mentioned. I also must admit that I absolutely dont know, what that is and also didnt found anything about it, while it sounded like something interesting at least…
Sorry, I guess that wasn’t the right video. 
I looked closely at the attached video, and it looks like the cause of the problem is lighting, but if not, it could be a phenomenon caused by Denoise.
This can be confirmed by performing a test rendering of the visible part of the current video without removing noise. 
Good idea, i`ll give it a try. But I cannot imagine that to be the case. While flickering with that intensity which looks like the denoiser interprets a light in one frame as “on” and in the other as completely “off”, looks more like a bug caused by the combination of volume scattering and lights, then a misinterpretation by the denoiser. But yes, only specific tests will give more information on that it seems.
Is light tree on or off?
It is on. Does switching it off, reduces quality or has other repercussions besides possibly be responsible for the flickering?
The dimensions of the light in the video, when combined with the noise of the fog, seem to have an effect. But I’m not sure… It’s speculation. There’s no other factor to think about
In a vast number of tutorials regarding mentioned fog, the dimensions are mostly identical. Based on real life scale you have according lamps as well as a big fog cube covering most/all of the scene. I never came across an issue regarding size in that matter, so I assume either a third component in combination with lights and fog or rather something completely different caused this.
It’s a kinda bonky way to sample lights faster, it can cause weird artifacts with lights in a semi-consistent way kinda like what you are showing, but if you aren’t using it, that ain’t it either!
I’m not an English speaker, so I think the meaning was conveyed a little differently.
Because the car’s headlight light size in the scene is small compared to the overall ratio, I wonder if there could be a problem with Denoise.
In the video, there is a flicker in the glowing area.
(We didn’t find any material similar to the scene you attached.)
Yeah, that might be the case. Whereby I will quit using volume scatter und try to imitate it with a depth pass somehow.
