Rendering a looping environment animation but the lighting changes in render?

[esteroid]

I’m trying to make a looping environment animation, and have keyframed the first and last frames to have identical settings. But for some reason, the lighting post render is making it so the first and last frames are slightly different. This is meant to be used for theater projection, so this kind of difference will be very noticeable.

first frame in scene

last frame in scene

first frame in render

last frame in render

having the end frame be just a bit brighter than the first one is gonna be a problem, but I can’t find out what’s causing this…

[glitchered]

is this using pathtracer or “regular” rendering? if it’s regular you gotta give it a couple warmup frames. lumen needs some time to accumulate light. the exact number is in a cvar somewhere.