"They can only stand red light."

This has to deal with the way that photography film, and the EM spectrum work. Red light is literally the weakest light we can see in(they also use it in submarines and such). If you go into a modern film room, to this day, it will have red lights.

It's an obvious reference, but its also not anymore weird than any others.

My point wasn't that it was weird. My point was that I didn't know why he did it, or what it meant, if anything. It seems rather silly to just pick random figures from the time and throw them into a book haphazardly, so I figured there might be some meaning or reason behind it(which I wanted to learn).