Shimmering GI in small gaps - Lumen Unreal 5.5

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I have this most basic lumen/GI question : I know that Lumen tends to react and bounce in every way possible when the gap between geometries is small. This causes certain issues with the distance precision. I’ve tried so many ways to correct it, but even Postprocess Lumen Final Gather quality does absolutely nothing, not any GI console command by this fact.
How do you deal with it? I need to stay in Lumen since the project comes to a close.

UnrealEditor_VfJKhk0pQI

Here in this gif are two cubes I’ve placed close to another in the original settings of Unreal to start exploring.

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Hello there @David.C.Code !

Yeah, Lumen can have a hard time with small gaps and crevices. Checking around the community, it seems to be related on how it handles geometry between meshes, not being precise enough.

You can test by disabling screen space traces, which will force Lumen to use the surface cache, resulting in a more stable visual. Go to the console, and input r.Lumen.ScreenProbeGather.ScreenTraces 0