Reflection capture cancels Skylight contribution

Trying to incorporate both a Reflection Capture and a Skylight in my Scene. My Skylight is Stationary with a Sky Distance Threshold set to 1.0 and Source Type set to Captured Scene.

After baking I adjust my Intensity Scale but the moment I enable the Box Capture it cancels any effect my Skylight has!

Does anyone know why?

Do you have an example? Stationary skylights provide diffuse and specular lighting. If you’re baking lighting, then the diffuse contribution is shadowed, but the specular is not and will still show whatever the capture is. You’re meant to replace it with reflection probes in interiors to overwrite the sky’s specular contribution, and with stationary skylights, there’s a visibility mask created to properly blend the sky light spec and the reflection probe.

If you’re doing this in an interior, setting the distance threshold to 1.0 is kind of pointless. The Skylight is meant to replicate the light from -the sky-, not an imaginary source in the center of the room.

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Thanks. My understanding of distance threshold is that it includes everything OUTSIDE of the threshold value when creating the reflection map.

Am I mistaken? Or is there some other setting elsewhere that determines how this works?

No, you’re right, it’s just if you’re setting the distance to only 1(meter, I’m assuming), then you’re saying whatever is at least 1m from the skylight’s position will be captured. If it’s in an interior, you’re most likely picking up the walls, furniture, etc. You can always double check by throwing a chrome sphere in the scene or looking at the Reflections debug view(may need to turn off SSR and other reflection probes if any).

I will say for dynamically-lit interiors where RTXGI, RTGI, Lumen, etc. aren’t available, a skylight with a low distance threshold can work in your favor for “faking” the bounce light since it’s just reprojecting the interior. But in your case you’re using a stationary light so I’m assuming you’re baking.

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