Original: Camera shutters Camera shutters can be fitted in two positions: Central shutters are mounted within a lens assembly, or more rarely behind or even in front of a lens, and shut off the beam of light where it is narrow.
Simplified: Camera shutters Camera shutters can be fitted in two positions: Central shutters are mounted within a lens assembly, or more rarely behind or even in front of a lens and shut off the beam of light where it is narrow.