Concerns Regarding the Phasing Out of Raytracing in Favor of Lumen in Future Unreal 5.4+

I think it’s pretty clear in Daniels linked post with screenshots
I need to find time to create comparison videos/screenshots but I’m mid project so can’t find the time.

Again main issues:

  • Lumen reflections are not as accurate nor as sharp as hardware raytraced reflections (depreceated). Even when using a mirror material (roughness 0 - 0.05) I get some sharp reflection and then moving blobs on top which seem like some sort of approximate samples of my surrounding environment.

  • Lumen shadows are much noisier and less accurate than their hardware raytraced (depreceated) counterpart. Where before I could just increase the number of rays on a light if the result was too noisey, doing the same with lumen doesnt seem to have any effect. This is most noticeable on large soft lights like rectangle lights.

Quite frustrating that it feels like I’ve loss quite a bit of control. While I appreciate for games etc the results are good enough, for me the quality drop is noticeable.

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