Flickering in Animation

[Otuama]

Hi all

Can anyone give me advice of how to fix this issue.

I'm getting flickering in a number if places.  The video shows the main culprits.

Using 4k cache mode - Animation preset - adaptive light solver = ON..

 I'm doing a test with adaptive light solver off which may solve the issue but thought I'd post here in case it doesn't.

The glass flickers at the very start.

The 2nd shot is the biggie.  Windows flicker and also white parts of the model do too.

The 3rd shot - it flickers on the side of the building

The 4th shot - it goes a bit crazy at the end

Thanks

[maru]

Could you please resend the original video? The artifacts are clearly visible, but the YT compression is killing any details. The best option would be contacting us here with the video attached:
https://support.chaos.com/hc/en-us/requests/new

First of all, with this kind of fly-through animation and only some minor moving objects like the 3D people, you do not need to recalculate the cache for each frame. The solution is to save the cache file only once and then reuse it for the whole sequence. You can learn more here: https://support.chaos.com/hc/en-us/articles/4528617365649

Secondly, I would advise using the UHD Cache instead of the 4K Cache. While they are generally both working fine, the 4K Cache is still experimental, so it may fail in some scenarios (this seems to be the case here...).

And lastly, at least some of the flickering (especially by the end of the animation) looked like something caused by overlapping polygons (Z-fighting). The solution to this would be inspecting the scene and making sure that the models are set up correctly.

[Otuama]

Thanks for the prompt reply.

Could you please resend the original video? The artifacts are clearly visible, but the YT compression is killing any details. The best option would be contacting us here with the video attached:
https://support.chaos.com/hc/en-us/requests/new

Will this weTransfer link be ok?  I've requested a Chaos password recovery but it's taking ages to come through.

https://we.tl/t-CnsZjtsCnu

First of all, with this kind of fly-through animation and only some minor moving objects like the 3D people, you do not need to recalculate the cache for each frame. The solution is to save the cache file only once and then reuse it for the whole sequence. You can learn more here: https://support.chaos.com/hc/en-us/articles/4528617365649

For this I calculated every 5th.  Maybe I've misunderstood the whole caching process for years.  What we do is normally cache every 15-25 (depending on the job) but with animated objects we go lower.

We also do cache's per shot (we generally do cut shots)

Secondly, I would advise using the UHD Cache instead of the 4K Cache. While they are generally both working fine, the 4K Cache is still experimental, so it may fail in some scenarios (this seems to be the case here...).

Great... Fantastic :(

If it is the case that it's because I've used 4K, I'll stick with UHD until it's considered stable.

For this job there's only 3 shots and they're long & winding.  The caching process was taking ages... I put it down to quite a few Anima characters (a lot 4D ones). 

So, I split the job into 11 shots.

This'll hopefully make it easier to just work on the troublesome shots.... I don't know anymore.  :D :(

And lastly, at least some of the flickering (especially by the end of the animation) looked like something caused by overlapping polygons (Z-fighting). The solution to this would be inspecting the scene and making sure that the models are set up correctly.

The white parts that flicker seem to be fine.  I've selected a face and deleted it.  Nothing intersecting.  I've made sure I haven't been a plonker and got a duplicate building overlapping.  I've also selected one of the white balconies detached it - a cube.... and it has 8 vertices.

--------------------

Thanks

[maru]

Thanks. I would recommend the following:
- Switch to UHD Cache
- Render a single UHD Cache file for the whole scene (regardless which camera you are rendering from)
How to:
1) Render Setup > Scene > set time limit to 1 second
2) Render Setup > Performance > UHD Cache > select "Animation (flicker free)" preset.
3) Precomputation: "Calculate from scratch"
4) After render: "Save to file"
5) Specify "Filename" path.
6) Start rendering. Corona will only calculate the UHD Cache, then stop and save the cache file.
7) Set Precomputation to: "Load from file"
8) Render your animation (all frames).

This will not work correctly only if:
- there are some large moving objects in your scene affecting the global illumination in a significant way (this is not the case in your animation)
- there are some large, intensive moving lights illuminating your scene (this is not the case in your animation)
- something like sun moving over the horizon turning day into night (this is not the case in your animation)

This should work fine in your animation because here we are dealing mainly with a camera fly-through and there are just some small moving objects such as the 3D people and cars which do not generally affect the lighting in your scene.

If this does not seem to work fine, please contact us again here, or even better at https://support.chaos.com/hc/en-us/requests/new , and we would be interested in checking your scene file if possible.