Deer Are Colorblind
It’s true that deer don’t see all of the same colors we do. Obviously, hunter’s orange doesn’t stand out for deer like it does for us. Still, they do see colors on certain parts of the spectrum quite well.
Deer can see blues and yellows clearly. It’s the reds and greens that they can’t pick up on. The term is “dichromatic.”
That’s not to say that you should dress as a Christmas tree when you head out to the stand, but it’s certainly a better idea that going as say a Easter egg.
Solid colors of any hue are typically a no-go, since those rarely occur in the natural landscape. Also, white is known to attract the eyes of a deer. Whitetails especially use the white under their tails to signal danger.