I just noticed that the Unreal engine calculates the color of light wrong.
If I make a light source 100% red - the overexposured area should stay red, no matter how bright the light is. However, the light shifts to a more yellow-ish color, and then to a white color. In real life this wouldn’t happen, because there’s absolutely no information in the green and blue channel.
The same goes for blue, but here it shifts to magenta, before turning white:
Green also seems to shift to yellow and then white:
This breaks the illusion of photo-realism a lot.
For the record, this is how it’s supposed to look like:
Hope this is something you guys can look in to, so that it’s easier to achieve photo-realistic results in the future =)