UE5.0 flickering shadow (lumen?)

https://vimeo.com/oviantales/download/741366208/1971e73821

Hello everyone
I tried to resolve this problem for an entire week and I even if I found some tracks and clues on the web, I could not be able to resolve this shadow flikering issue.
Any idea ?

Every light in the scene is movable.

I tried to enable Distance Field Shadows on every lights, enter r.Lumen.Reflections.HierarchicalScreenTraces.MaxIterations 4,
I also switched from Virtual Shadow Maps (Beta) to Virtual Shadow Maps but it didn’t work. I think I am lost now…

Project settings :

Dynamic global illumination Method : Lumen
Reflection Method : Lumen
Use Hardware Ray Tracing when available : on
Software Ray Tracing Mode : Detail Tracing
Shadow Map Method : Virtual Shadow Maps (Beta)
Support Hardware Ray Tracing : on
Ray Traced Shadows : off


Post Process Volume settings :
Global Illumination : Lumen
Lumen Scene Lighting Quality : 2
Final Gather Quality : 2
Final Gather Lighting Update speed : 1
Ray Tracing Global Illumination Type : Disabled
Indirect Lighting Intensity : 0.05
Reflections method : Lumen
Lumen Reflection Quality : 4
Screen Space Reflections
Intensity : 80,73
Quality : 100
Max Roughness : 0,5
Ray Tracing Reflections
Max Roughness : 0.8
Max Bounces 5
Samples Per Pixel : 1
Shadows : Hard Shadows
Include translucent objects : off


Export settings :
Sample Rendered with Movie Render Queue
4k, png sequence 25fps

Anti-Aliasing
Spatial sample count : 1
Temploral Sample Count : 32
Override anti Aliasing : on
Anti Aliasing Method : None

Console variables
r.AmbientOcclusion.Denoiser.TemporalAccumulation 0
r.GlobalIllumination.Denoiser.TemporalAccumulation 0
r.Reflections.Denoiser.TemporalAccumulation 0
r.Shadow.Denoiser.TemporalAccumulation 0

Omg, please take a look:

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Thanks a lot for your help but unfortunatly, it doesn’t seems to solve the problem. I did changed my AA and lumen settings and it is still flicking exactly the same way…
Could it be inside the movable lights settings ?

mm and what about the updates in advanced?
image
Raytracing reflection? Just lumen?
The lights are using raytracing?

mmm I see some things so so… like:
r.Tonemapper.Quality 5
r.ScreenPercentage 150
r.RayTracing.GlobalIllumination.SamplesPerPixel 4
r.ReflectionMethod 3
r.TemporalAA.Upsampling 0

r.AllowStaticLighting=True?
r.RayTracing.Shadows=False?
r.UsePreExposure?


And no, the lights are not using raytracing

Thank you very much, Alberto. I’m gonna try that right now

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r.Tonemapper.Quality 5
r.ScreenPercentage 150
r.RayTracing.GlobalIllumination.SamplesPerPixel 4
r.ReflectionMethod 3
r.TemporalAA.Upsampling 0

Just tried theses commands but no succes. I also crash using screenpercentage 150, even with my GeForce 3080…

Gonna try the last commands and see what happens
Thanks again for your help !

Hello Alberto
After a lot of experiments with PPV, console commands (24 unsuccessful renders haha) I finally found a solution :

First, I replaced my DefaultEngine.ini with a UE5 default project file (the one I was using came from Rural Australia demo), then I changed my PPV and MRQ settings according to William’ s videos (lumen explained and MRQ settings part01)

But I also added theses commands :

r.Lumen.ScreenProbeGather.ScreenTraces 0
r.Lumen.Reflections.ScreenTraces 0

It just solved the problem, no more flickering shadows !

Huge thanks to William and to you Alberto, for your more than welcome help
I can now move to the metal reflections :slight_smile:

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mmm not sure but I would say you are not tracing reflections :smiley:

well to be honest I see no difference
I found this:

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