Quote Originally Posted by flatulent1 View Post

The film window in the camera back is a wonderful thing. My Canon F1 doesn't have one; I can't remember how many times I've had to remove the lens, set the shutter to bulb and fire the thing so I could peer inside just to see if it was loaded, nevermind with what.
Well, there's another way to find that out: turn the rewind crank in reverse without pushing the button and if there's film in it, it will tighten up.