Sitting on stand one afternoon a couple of years ago. I look across the river and at 200 yards their stand a real nice buck. I grab my binoculars and set their just to watch him. The wind is blowing about 5-10 directly toward him. As he approaches the river he starts putting his nose in the air testing the wind. I could tell he was picking up something he didn't like. I had showered with "Dead Downwind" but he still picked me up. He just turned and walked away, went about 300 yards downriver and swam the river and came over to my side and headed away from my stand location. It's amazing how far away they can smell, 200 yards in this case.