Software: UE 5.7
Rendering Display Mode: Path Tracing
Default display with no console commands (default r.PathTracing.VisibleLights 0):
Display after enabling the console command r.PathTracing.VisibleLights 1:
The problem shown in the images: The RectLight source itself becomes visible. Previously, in version 5.4, using this command would only display the Skylight’s HDRI background image; the RectLight source would not be visible.
Ugh… This has a significant negative impact on product rendering when adding fill lights!!!
Therefore, I checked the help documentation and found the following:
Help Documentation Note:
1: Make all lights visible to camera.
Well, according to the documentation’s description, fixing this behavior is technically correct.
However, this is not what rendering artists want. It makes adding fill lights very problematic. Fill lights can no longer face the camera directly; they must be placed facing away from the camera, otherwise they become visible.
Therefore, I believe they have fixed a bug that should NOT have been fixed.
!!! Please, EPIC developers, revert this change and include the fix in the next minor update. Thank you.