The issue with foliage Render in Unreal Engine 5.2

I am trying to render a forest scene video. I am noticing a lot of shadow flicker. And I can also see Gi update as the camera zoom out. Gi Update shouldn’t be that slow and noticeable. Please let me know if anyone knows some console commands to avoid shadow flickering and notable GI updates on trees.

  • RAM: 64 Gb
  • GPU: RTX 4090 (24 Gb)

This is new for you in 5.2?

No, I am already aware that virtual shadow maps are in beta so it will take time before it gets stable and production ready.
But for time being i am looking for a work arround

VSMs are considered a separate system from lumen, and GI in general. If you disable lumen, do you still have this issue?

I don’t want to disable lumen and i wasn’t having this issue before lumen

Unfortunately then, you may be out of luck. Lumen is an imperfect solver for foliage, and that sort of wide dollying shot is the exact sort of thing that can cause problems. That being said, if you can send a few screenshots of what your surface cache looks like, there may be an easy fix for this.

Essentially, there’s a chance your lumen scene representation is simply too small, and that fizzling could be things entering and leaving the scene. In that case, you can raise the lumen scene detail to attempt to fix it.

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thanks, I will try that

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Maybe to some help Foliage Grass flickering in the shadow UE5 Lumen

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