Mine are in well established travel corridors, so i know there will be alot of pictures there. So i leave mine out 1 month at a time. Besides it costs $30 in gas, 5 hours of time, and 3 miles of walking to check them, so i try not to do it too often. And i don't like to leave my scent going in or out every few days or week and educate them too much.

During bow season if i happen to be passing by one of them i will check them as long as it's been sitting at least a week.