Where I am, "200 square inches" of hunter orange is a must (for my small game hunting, anyway); but orange camo (for whatever reason) is not permitted. I've read articles that support what others have already said regarding hunter orange not being any more visible than any other "earth tones" (to the animals). Any time I lose a shot on a squirrel, I'm certain it's not my orange hat, but instead my clumsiness in the underbrush that draws their attention. I have seen some videos from guys in the UK who hunt rats, and they say that the color blue stands out to rats like lights in the darkness. I don't know the "truth of science" behind that, but if I ever hunt rats, I won't be wearing blue jeans.