Animation Flickering

[willmorris3d]

Hello,

I am rendering a huge animation and rendered out over 8,000 frames with zero flickering, but my swimming pool scene is causing me random flickering that I cannot solve. not sure if it is a bug. Its driving me mad.

All my settings are pretty much default with UHD cache set to Animation (flicker-free). noise set to 3.75%

I am using using very latest, Corona render, and using Phoenix for pool water, anima , forest and railclone. i am rendering on 17 different render nodes/machines, all of which rendered previous 8000 frames with zero flicker.

If you watch the link you can see the flickering top left hand corner.

I was getting flickering in bottom left hand corner, but i merged into a new scene to see if that would fix it and the flickering completely moved to a different place, which is why i think it may be a bug.

i have deleted all lights and re added them, checked for hidden or duplicate objects/face etc, reset settings etc.

for the life of me i cannot not solve it, I am able to send scene if anyone from corona would like to take a look? or give me an idea what is causing it?
 
Many Thanks

[TomG]

Have you tried the 4K Cache instead? Generally it's better and faster in most cases.

[Nejc Kilar]

Have you tried the 4K Cache instead? Generally it's better and faster in most cases.

This but then what you could also try doing is upping the precision of the UHD Cache to 2 or 4 or just something higher. I find it that also helps although it does increase the pre-calc times obviously.

[Tom]

I always use Path tracing for both solvers and never had an issue with flickering.

[maru]

That looks like GI flickering, so it could be the UHD Cache, but we can't be sure about it. Would you be able to send this scene to us for investigation?
https://support.chaos.com/hc/en-us/requests/new

As the first step I would try enabling the development/experimental stuff rollout (https://support.chaos.com/hc/en-us/articles/4528523195537) and:
- disabling "Adaptive light solver" under "Lights" - then check if the flickering is still there
- changing "Enviro sampler" to "NormalDep Compensated" - then check if the flickering is still there
Those are shots in the dark though.

I always use Path tracing for both solvers and never had an issue with flickering.

This can severely slow down the rendering, especially in interiors.

[davemahi]

I always use Path tracing for both solvers and never had an issue with flickering.

This right here. I never ever use anything but Path Tracing for both solvers. And it makes your life easier not having to worry about old outdated render GI options.