Quote Originally Posted by Outdoorsman
Yes, absolutely do cover the viewfinder when advancing the roll! You can easily check the light spillage by putting on the body cap, turning on the camera, activating the meter and then aiming the viewfinder at something bright. Then cover the viewfinder with something.
But when you trip the shutter, the mirror rises, blocking off the viewfinder.

So how does light entering the viewfinder get past the raised mirror, and onto the film?

Answer it doesn't.

Simon