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500 CM lockup


New Member
While out shooting this weekend, I was on frame #9 of a roll if film and went to wind on to the enxt frame after taking a shot. The winder moved as normal, but at the next frame, the shutter would not fire. I'd tripped the mirrow lock up button okay, but the shutter would not fire. The darkslide was removed. I tried to re-insert it and it would not go back in. Obviously the film back could not be removed.

What I did was crank through the film to make that safe at least, and removed the film back insert. I left the film back empty, and re-inserted the insert. The whole camera was locked up. I could not remove the lens, the mirror was locked up, the shutter would not fire, and I could not remove the back. The worst scenario to be in!!

Anyway, I did not force anything, but did manage to get the camera unlocked by re-pressing the mirror lock up button, and letting it go. Somehow, that was enough to free something up, and the whole mechanism unlocked itself. I have never seen this type of lock up ever before, and feel it is different than the usual lock-up most folks experience that can normally be fixed by a screwdriver. The camera is very clean, and was always maintained prior to me buying it.

Has anyone ever seen this type of jam before, and knows what maybe causes the problem?

Hi - I facing a similar issue with my 500c. The winder just stoped half way through and wouldn't move any further.

Please help. I just got the system 3 days back as a gift from my uncle. it is at least 30 years old.

Sorry to read that your camera is locked after only three days of use.
These cameras are all mechanical systems that need a service from time to time.
A 500C body is at least 37 years old it can even be 50 years old.

Most of the time these can be unlocked with a little extra help.
If the camera is fitted with a lens and filmback, remove the filmback, take a small screwdriver, open the lower part of the auxilary shutter, just below the lens there is a little screw turn that gently to the right and press the lens release button to remove the lens. Be carefull not to let the screw driver slip as it may damage the rear lens element.If the screw is seized the cause may be a defective lens. Do not use force but let a camera technician do the job.

Chances are the auxilary shutter causes this problem or any other spring operated part of the camera.
A broken spring or just dirt and old sticky lubricant are most likely causes for a jammed camera.
It will need a service to make sure this does not happen again.

For amateur use a service every 3-5 years will do.
Professionaly used cameras that are used daily will need to be serviced once a year.