Appendix L Rollfilm and sheet film cameras

The great majority of modern cameras use 35 mm or APS film, but other cameras are made to accept larger picture format rollfilm or individual sheet films. You will also find many older, second-hand cameras needing films of this kind.

Unlike 35 mm material in its light-tight cassette, rollfilm comes on an open spool attached to light-proof 'backing paper' (Figure L.1). Film and backing paper are rolled up tightly together so that light cannot reach the sensitive surface during loading. Inside the camera they wind up tightly onto an identical take-up spool after exposure, ready for unloading. No rewinding is therefore required.

The main rollfilm still in general use is 120 size, which allows pictures 6 cm (2/4 in) wide. Rollfilm cameras (often termed medium-format cameras) may give twelve pictures 6 x 6 cm to a film; others give ten pictures 6 x 7 cm or sixteen 6 x 4.5 cm.

Negatives this size need less enlargement than 35 mm film so you can make big prints which are relatively grain free.

A few large-format cameras use individual sheets of film, typically 4 x 5 in. Each sheet has first to be loaded into a film holder in the dark (see page 326). Using sheet film allows you to process each exposure individually, and the still larger negative gives even finer grain and detail.

Figure L.1 How the start of a 120 rollfilm is attached inside its light-proof backing paper.
Figure L.2 Rollfilm twin lens reflex camera. S, shutter speed control; R, release for shutter; A, aperture control; V, viewing and focusing screen; M, mirror (fixed); E, exposure counter at back of camera; F, focusing control; L, lightsensitive film.
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