Ok, my dad has an Olympus SLR film camera. I don't know the exact make, but this was one of the first cameras with an onboard microprocessor to measure the light levels (you set the F-stop on the camera, and it would calculate the exposure time.) Anyways, when there was no film in it I could click the shutter and the mirror would flip like it should. The only problem now is that the mirror is "stuck" in position. It will not move when you hit the shutter button, and I tried to GENTLY push it into it's origional position, but that didn't work. One other thing - the batteries are currently dead. I need to get replacements. Is the mirror issue probably caused by the dead batteries, or is something more serious wrong?