single-lens reflex (SLR) camera: camera back

film cartridge chamber

Compartment that holds a film cartridge.

film guide roller

Rotating cylinder that directs the film from the cartridge toward the film guide rails.

film guide rail

Each of the flat metal rails on both sides of the focal plane shutter; the taut film travels along them.

film leader indicator

Indicator showing whether the film leader (end of the film extending outside the cartridge) is properly inserted into the take-up spool.

pressure plate

Spring plate that keeps the film flat as it passes behind the lens.

film sprocket

Small serrated wheel that guides the film toward the take-up spool.

neckstrap eyelet

Small ring that holds a strap to help carry the camera.

take-up spool

Cylinder for winding the exposed film.

focal plane shutter

Opaque device that opens for a predetermined length of time based on the shutter speed chosen; it allows light to come in contact with the film.

viewfinder

Device for viewing the scene to be photographed, framing it and adjusting its clarity.

film rewind system

Manual or motorized device that winds a partially or totally exposed film back into its cartridge.