I used to climb down when I couldn't see the forrest floor 10 yards out anymore. Spooked a few deer that way. Now I wait maybe a half hour after dark and if I don't hear anything. I'll get down. At least a half dozen times, I've been stuck in the tree an extra hour or longer because of deer getting underneath me right at dark with no ETHICAL shot. Either had to wait them out, or spook them. One night I'd climbed down at dark, heard something behind me which I feared might be my favorite bear, only to see a ten point staring into myheadlamp. Game over[:@]