(UE5) Point Light fading out when turning the light off

I have a movable point light in my scene that is controlled by a light switch. This C++ function is called whenever the light switch is pressed:
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However, whenever the light is turned off by this function for some reason the light turns off with a fading out effect:
ezgif-3-062e2da0de

I have already turned off auto-exposure in the project settings so that cannot be the cause of this issue. The light is also fully dynamic as I have set it to movable. I also turned off any and all auto exposure settings in the post process settings on my camera. I’m also using Lumen to light my world.

I’m very puzzled by this issue so any suggestions would be greatly appreciated.

I don’t have a proper answer as my experience with Lumen is quite limited… However, could it be as simple as Lumen is faster at turning on the full brightness than lowering it?

Have you looked at the post process settings regarding the Update Speed?
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A way to solve the issue ignoring Lumen as is: is to gradually lower and increase the brightness with code until you are satisfied with the result.

it’s the indirect light bounces that takes some time to add/remove
Don’t think there is any other way to fix it other than turning off the indirect lighting, but changing the lumen update speed might help.

But in a completely lit room like this, it could be possible to turn off the indirect lighting and make it seem almost identical

I tried turning off the indirect lighting on my point light but there was no change at all unfortunately.

Yeah, thst’s because of Lumen and its speed. Those 2 speed parameters could help (or you should find the speed related cvars).

Anyway, more speed → less performance.