Hi all!
I’m adding some flickering lights to my game, and I’m getting this noisy ghosting light pattern on surfaces when the light flickers. This only seems to happen when it’s flickering at a faster speed. Pulsing slowly looks fine. Here’s a video of the issue: https://streamable.com/mhyuha
Engine version: 5.4.4
Using Lumen with raytraced shadows off.
Lumen uses temporal accumulation to cleanly resolve. In other words, it takes multiple noisy images over several frames and blends them together to get a noise free image. If you flicker a light faster than the lighting can update, artifacts and noise are inevitable. There are some settings like the update speed and many cvars that can change the quality you could experiment with but this is ultimately a limitation with how the tech works. Nvidias ray reconstruction tech also sets out to improve this flaw in raytracing tech such as Lumen for DLSS compatible GPUs.