One of the biggest causes of jamming cameras is the locking-cable-release. Avoid buying any cable release with a small screw-down disk that becomes a time-exposure lock when it is released. They are always unscrewing and locking up your camera. They can fire off a whole roll of film in a camera with a motor drive. Purchase only those cable releases with a locking screw on the side. You can always put a tiny drop of instant glue under the locking disk of the trouble makers. Don’t use too much glue, which can bind up the whole thing.

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