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UE5 - Shadow flickering in higher resolutions render

Hi, I’m constantly having the same issue in different scenes and situations in UE5. When rendering the same scene in various resolutions there are flickering shadows bug appears after some point. Here is the example:

It does not matter if I use movie render queue or renderer in sequencer.

After some experiments and tweaking like making all materials two-sided, moving lights farther from geometry, or turning off shadow casting from some lights, the situation can become better but not completely fixed, and “point” after this issue appears again moves to a higher resolution.

The question is why the same light setup works differently in various resolutions, and where can I look to try to find a solution.

Are you rendering at a higher resolution than your monitor?

no, sometimes getting this with pretty low resolutions
my specs are AMD Ryzen 9 3950X / 32GB / GTX1080Ti / Win10 Pro

btw, i’ve been suggested a working solution for this problem:

r.Shadow.Virtual.ResolutionLodBiasLocal 1

4 Likes

Thanks for that console “hack” :wink: I can confirm it helped me with my problem.
I had correct shadows in my Viewport. As soon as I maximized it with F11, the flickering started.

First I thought it’s the same issue, like with those one sided meshes, but it doesn’t matter if you have fully wrapped objects or not.

Probably useful to mention; I’m rocking an RTX 2080 (with the good old 460.89 driver).

Cheers