As more sensitive photographic materials became available, cameras began to incorporate mechanical shutter mechanisms that allowed very short and accurately timed exposures to be made.
Many extension sockets will allow a plug to be inserted upside down, i.e. only the earth pin, defeating the shutter mechanism.
By the end of the 19th century spring tensioned shutter mechanisms were in use operated by a lever or by a cable release.
Also, wide-angle lenses for narrow-gauge movie cameras had to be of this type because of the shutter mechanism that had to fit in between.
Finally, the crude advance and shutter mechanism can result in images that are not properly centered or exposed.
The shutter mechanism was not without its problems, however.
The end of the film ran through the shutter mechanism and trailed down to the floor.
Imagons do not typically have shutter mechanisms and are instead mounted on shutters (i.e. Copal large format shutters).
This removes the camera-shake from the large slapping mirror inside the camera, but does not prevent camera-shake caused by the shutter mechanism itself.
The problem can be corrected by a knowledgeable technician without replacing the shutter mechanism.