I've had deer wind me at 200, but I've never seen them wind me from further. I practice scent control, but if they are still looking for you they will find you if your scent stream is hitting them. I hear guys tell me all the time that they have deer down wind and they don't get busted, well that can be explained by a couple things, 1 your scent stream is flowing above them, this normally happens in the mornings when the thermals are carrying your scent up. 2 they feel they are in a safe area and are not concentrating on detecting scent. This happens a lot after deer have moved out into an open field and feel comfortable feeding. 3 you don't know which direction the wind is blowing or you're not familiar with the wind currents in the terrain you are in.
Learned that after watching bird dogs some days point birds from 20-30 yards on good days. While the same dogs would have real problems on the hotter, drier days. They would have to be right on top the birds to find them.
I am sure its the say way for deer.
Ozark Chinquapin Foundation
American Chestnut Cooperators Foundation
"When a hunter is in a tree stand with high moral values and with the proper hunting ethics and richer for the experience, that hunter is 20 feet closer to God." Fred Bear
The one that blows me away is one drop of blood in the ocean can be detected by a shark at over a mile. I've heard the polar bear 30 miles as well...amazing. I would bet they can detect the smell for as far as the scent carries and that's going to be based on temps , terrain and wind. Wouldn't be surprised if on flat ground in the right temp and wind it's a mile+ , but that doesn't mean they know where you are, just you're somewhere. I believe they can tell if you're close vs far though. I've been busted at 200 yrds and not been busted as one has walked a circle around the tree I was in. Younger the dumber.