Getting rid of hot pixels / fireflies in Unreal Pathtracer renders?

Development Rendering
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I’m currently rendering some pathtracer scenes and am disabling Unreal’s tone curve in the render settings to get maximum quality for color. However, disabling the tone curve or having the ocio config enabled gives me a ton of hot pixels / fireflies in the bright reflection areas.

Is there any console variable I can add or method of getting rid of this in Unreal?

I’ve tried every noise reduction, dust and scratches, dust buster effect outside of Unreal in Davinci and After effects but none seem to work without ruining the image.

Screenshots of my settings and examples below!

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Hi there @LUNCHBQX. Hope you’re well!

This topic has been moved from International to Rendering.

When posting, please review the categories to ensure your topic is posted in the most relevant space.

Thanks and happy developing! :slight_smile:

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Hi, have you tried increasing the samples of any movable lights you have in the scene or your reflection samples in the post process volume?

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I am trying to sort the same issue. Running UE 5.3.2
I have tried increasing samples on everything I can find.
PostProc:
RayTracedGlobalI llum 32
Ray Tracing Reflections 16
Path Tracing Samples Per Pixel 512
Path Tracing Max Bounces 4
Denoiser is OFF - cannot use that for VFX production
Bloom OFF
Lens Flares OFF
Vignette OFF
Max Path Exposure 3
Exposure Min EV100 0.0 Max EV100 0.0 (so the color/values are not adjusted by UE)

My Light is just a dome light with an HDRI and the sun is clamped to 3 so not crazy high values there either. ANd I have a directional light value 1.9
LOTS of fireflies, all that stuff did nothing.

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But if I turn the Directional light OFF the fireflies are gone…

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I tried putting an area light 20,000 units away and up in the sky and made it 40,000 cd bright with attenuation at 100,000, to match the illumination given by the dir light and … the fireflies are back.
Hmmmm…
Any suggestions on the settings on the lights that might be causing this?

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I saw your shorts on youtube and aparently you managed to solve the issue somehow, can you please explain how ?

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