The standard 8mm film format was developed by the Eastman Kodak company
during the Great Depression and released on the market in 1932 to create
a home movie format that was less costly than its predecessor 16mm.
The film spools contains a 16mm film with twice as many perforations along each edge than normal 16mm film that is only exposed along half of its width.
When the film reaches its end in the take-up spool, the camera is opened and the spools in the camera are flipped was swapped (the design of the spool hole ensures that this happens properly). The same film is then exposed along the side of the film left unexposed on the first loading.
During processing, the film is split down the middle, resulting in two lengths of 8mm film, each with a single row of perforations along one edge, hence fitting four times as many frames in the same amount of 16mm film. Because the spool was reversed after filming on one side to allow filming on the other side the format was sometimes called ‘Double 8’. The frame size of regular 8mm is 4.8mm x 3.5mm and 1m film contains 264 pictures. Normally standard 8 was filmed at 16 frames per second whereas better cameras could vary the speed.
The common length of film spools allowed filming of about 3 minutes to 4.5 minutes at 12, 15, 16 and 18 frames per second.
Kodak stopped selling standard 8 mm film in the early 1990s but continued to produce the film, which was sold via independent film stores. Several companies buy bulk quantities of 16mm film to make regular 8mm by re-perforating the stock, cutting it into 25 foot (7.6m) lengths, and collecting it into special standard 8 mm spools which they then sell. Re-perforation requires special equipment.
Movie cameras, had an upsurge in popularity in the immediate post-war period giving rise to the creation of home movies. Compared to the pre-war models, those cameras were small, light, fairly sophisticated and affordable.
a basic model might have a single fixed aperture/focus lens, a better
version might have three or four lenses of differing apertures and focal
lengths on a rotating turret. A good quality camera might come with a
variety of interchangeable, focusable lenses or possibly even a single
zoom lens. In the 1950s and for much of the 1960s these cameras were powered
by clockwork motors, again with variations of quality. A basic mechanism
might only power the camera for some 30 seconds, while a geared drive
camera might work for as long as 75 - 90 seconds (at standard speeds).