Unreal Engine 5.7.1 Lumen Ghosting/Light lines help ._.

Hello everyone, I need some help.

I have some experience with Unreal Engine 4.27. I am currently returning to working with a newer version of this engine (5.7.1) to do a certain project. So Lumen is new to me and I need to figure it out.

I currently have the problem shown in the video. I understand that Lumen will naturally cause some ghosting, but these lines are a bit too much… they are too visible and distracting.

I tried various methods to see if I could somehow eliminate or at least reduce the effect. I set Lumen to the highest and lowest settings, but the lines are still there. I also turned off motion blur and tested other anti-aliasing methods, but still nothing.
I also tried to brighten the shadows in post-processing to reduce the contrast and even turned off the shadows on the directional light, but it still didn’t help.
Finally, I turned off Lumen and suddenly the lines were gone.

I’m working on deferred rendering because the scene will mainly have dynamic lights, so I wanted to use Lumen…

Maybe I’m looking in the wrong place, I don’t know.

Has anyone else had this problem before and maybe found a solution?

Video:

Unreal engine 5.7.1 Lumen problem video link

Like all raytracing it has artifacts, slow to get to full quality, limited tracing distance, this just looks like there is a delay in quality transition. Some of it can be attributed to TSR or TAA using previous frames and the quality of the GI setting. I wouldn’t worry about it in this early stage of your project, Lumen like all Raytracing solutions has it’s problems due to it being very GPU intensive and being done in realtime.

Thank you for your reply. It didn’t occur to me that it could be a matter of the nature of ray tracing itself…

You could try adjusting the Lumen settings in your post process volume but just bare in mind that can come at a cost in performance