Need help with (noise?) artefacts on my stylized grass

Weird (noise?) artefacts on my stylized grass

Hi!

I’m quite new to Unreal and been working on some stylized grass!

Recently I started to work on lighting / rendering and noticed, that in darker shadows or in lower light scenes there are noisy artefacts on my grass.

This is how my grass should look like →

This is how it looks at low light conditions →

The noise that is visible is also moving; not in a certain direction, just random noise.

I’ve been also struggling with the resolution of my landscape, might have something to do with the noise?

This ist what I mean, the lights seems to have a “low resolution” and instead of a smooth gradient between light & dark spots, there are multiple steps->

I guess this is because of the landscape texture resolution? Is there a way to increase the resolution or do you know any best practices? →

I use a very basic lighting setup; directional light + SkyLight with cubemap (GrayLightTexture).
Basic landscape, basic stylized grass that gets the base color from a runtime virtual texture. Grass model just consists of some low poly blades of grass.

  • Already disabled all light sources and checked, if its a certain source that is causing the noise
  • Checked all parts of my grass material; checked everything that uses noise like wind effects

Let me know if you need any further information!

Sorry for all the questions! Thank you for your time!