1 The Director of Photography – an overview

The motion picture camera 47
Figure 4.10 Typical layout of a film
camera
Figure 4.11 The layout of a film
camera using clip-on magazines
Film camera layout
There are many individual layouts for a film camera, but Figure 4.10
shows the basic principle of most of them. Once the film magazine is
fitted to the camera, the loop coming from the camera can be laced
through the camera mechanism. It usually has to pass over a sprocket
wheel, shown as the dotted circle, and is kept in place by lay-on rollers,
shown as the grey circles. Having left the sprocket, the film forms the
film feed loop; it then passes through the film gate, with its associated
aperture and claw mechanism, and so on to the take-up loop, back
over the sprocket, and finally returns to the magazine light trap.
Some cameras employ a quite different layout, where the main
sprocket and the back pressure plate of the gate are contained in
every magazine. In this instance, the claw mechanism must be in front
of the gate. One configuration of this layout is shown in Figure 4.11.
During fitting the magazine, shown in the darker grey, slides horizontally
towards the camera body, shown in lighter grey. Clearly, the loop
Feed
Roll
Take up
Roll