daddyflea, your talking the human eye that sees in full color, with full camo your son blends right in to the human eye that's why he is so hard to see.
Other animals don't see what we see when it comes to color. They rely more on movement.
I have called coyotes up close and they have looked right at me knowing something is there, but yet they don't run. Why is that? I'm not moving.
Big game hunters well tell you the same thing, they know something is there but as long as you don't move the animal won't spook, unless they wind you, but that's another story lol....Good hunting