Originally Posted By: South Edisto ManNewby question. How would the comparison turn out if it were 90 degrees outside instead of -12 degrees. As it stands there's almost an 100 degree difference in the body temperature of a deer and the temperature of the landscape. All of my hunting would be closer to 90 degrees and 90% humidity. Humidity is the great equalizer of all thermals. It can turn really great thermals into average thermals, and can make some thermals virtually useless. 90% is fairly high, but every thermal I own can see an animal in 90% humidity. If it couldn't, I wouldn't own it.
You will still be able to pick out features of a deer with a decent thermal in the summer and with 90% humidity. Here was a warm September day and you can see this coyote just fine. I am using my PTS536.