Artifacts/Flickering Grass_UE5_Movie_Only Skylight_Lumen

[anonymous_user_dc735dfb]

Hey Guys,

I have an issue that I really cannot solve, and it´s getting really frustrating, perhaps somebody can support?

I have an ArchViz project, UE5, Lumen enabled, no directional light and only Skylight. Skylight set to movable, as all the objects. The grass creates the following artifacts when rendering movies, and I cannot find out why? I found out it is created by the skylight after some testing. I also tried activating different options in the grass settings, as remove the contact shadows, remove the affect distance field lighting, or ativate the cast shadow as two sided option, without success - either the grass looks completely fake, or the flickering stays there.

External link GIF in case the UE one doesn´t load

Any ideas of what could be causing it, and potential solutions?

Thanks!

[S-Dot]

Lumen in Unreal 5 doesn’t support every unreal feature yet. It doesn’t support foliage, vertex shaders used for moving grass, the skylight has some restrictions and isn’t really meant to be your main lighting source afaik.
There are 2 long videos on YouTube in Epics channel about Nanite and lumen that explain in detail what’s possible right now.
Is the grass foliage? Does it use World position offset? Is Nanite enabled for it? Is it flickering with a dynamic directional light?