Quote Originally Posted by Bill Burk View Post
I have a theory that fits this.

The film didn't catch the takeup spool when first loaded... but after some 20-or-so shots, it FINALLY caught and started winding...

So it might have been good to go, but OP rewound and sent the film in for processing.

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All good advice to check the wind knob is turning as the shooting progresses. Good to check that the camera can make it through a roll of scrap film when properly loaded... But chances are... Next time you shoot... You'll get a good roll of film.
That's the same thing I was thinking. It's easy to have the film pop out of the take-up spool. I keep my "36 frames on the leader"-oops roll around as a warning for the future, the film equivalent of Cromwell's head on a pole. I should probably cut and sleeve it, put it in an 8x10 frame and hang it on the wall.