Canon AE-1 Program – film advance check
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I loaded a roll and made sure the film leader was properly caught, but I noticed the rewind knob wasn’t turning when advancing the first few frames.
I gently turned the rewind knob to take up the slack until I felt some tension. After arming, the knob turned again. But after few hours, at the next rearm the knob didn't turn. I did the same test once again and the knob turned at the following rearm (by 180°). What’s the best test to confirm the film is actually advancing correctly? Is it worth opening the back to check, or should I avoid that and try something else first?
I'm carrying the camera in the bag, maybe the knob is loosing tension while moving in the bag?