I programmed a quick-and-dirty time-lapse photography calculator, and by using a 60 minute blank tape, and by shooting 0.55 seconds (the shortest time available) every 10 minutes (the longest interval) I can cover a period of 45 days! I think I can shoot at extended tape speed and get 90 minutes of recording. If that is true I can cover 68 days! That is 2.3 months!