Any new tips on reducing fire flies/white hot spots/ hot pixel issues with Path Tracing?

Development Rendering
1

I’m currently using UE5.5 with a Nvidia 5090.

I was going crazy yesterday trying to figure out how to get rid of the fire flies in my path tracing MRQ renders. Of course, the first step is to clamp thing in Max Path Intensity in the post processing settings. However, I was still getting them a little bit.

Raising samples didn’t completely git rid of them.

Using the denoiser just turned them into bigger white squares that would pop in and out.

The place they seemed to show up the most was around hair, particularly eyelashes. They’d pop in and out and just shimmer. This was on a character from Character Creator 5 and animated in iClone.

I ended up disabling all the denoisers except Optix and it managed to give me usable results.

I’d love to hear any other ideas of how to better handle these.

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Try using the graphics card drivers version 577

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Did you also increase the samples of the lights in your scene?

Is adaptive sampling turned on? This can cause some issues with undersampling.

NNEDenoiser does a pretty good job if you change the profile it uses to HighQualityAlpha.

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