Deer have an amazing ability to adapt. If you shoot often they will get used to it and pretty much ignore it. when I built my log home the deer got so used to my nail guns (the gas operated ones that fire like a gun) that they didn't even bother to look when I was firing nails. I shot a doe one evening about five minutes after putting down my nail gun. This was after shooting off a roof and firing nails as fast as I could for hours. I shot a ten pointer one evening while he and I were listening to two guys talking while they were loading their quads on trailers. Deer get used to things. It's the unusual things that really put them on guard.