Texas Bow,---Yes, we have seen this happen and it is mostly that the area across from your cam probably has the sun warming it up from the cool night air. and when the sun goes down the warm folage cools. Both of these events can be sensed by the PIR function of the cam. To correct this we placed the cam in an area where the background is at a greater distance during the warm weather periods. Now that we are in the cool season the weather "falsing" has not been an issue. The degree of sensitivity will vary between cams also. We have several out and only one has that degree of sensitivity to where we have to be careful where we place it. We use the rechargables in our Moultries with solar panels and the battery life has been very good. For the price they are just great cams and it allows just about everyone to enjoy the use of scouting cameras. Bill