Hey Harrythe1st,
So I need a bit more information in how you got to this point. I am assuming you opened a copy of this project in 4.15?
Your scene looks like it might need the ‘Auto-Exposure’ setting re-adjusted. We did make changes to the tonemapper’s default settings as well so make sure you have accounted for those changes as well.
Can you find a way for me to reproduce this in a blank project?
Thanks,