The only problem with leaving 120 film in a 'camera' was using a Calumet roll film adapter for 4x5 cameras. The film gets bent opposite of its natural bend, and if left in that position for a relatively short period of time (overnight), the film keeps the opposite bend and is difficult to roll tightly. I had to unload the roll film back in a darkbag since light would sneak in the ends oft h e roll since it was not rolled up tight.