|Photo by Patricia Poon|
The term 135 (ISO 1007) was introduced by Kodak in 1934 as a designation for the cassette for 35 mm film, specifically for still photography. It quickly grew in popularity, surpassing 120 film by the late 1960s to become the most popular photographic film size. 135 camera film always comes perforated with Kodak Standard perforations.
Image formats on 35 mm film are generally 24 mm wide, between the perforations in the 35 mm wide film. The common "full-frame" image size is 24×36 mm (thus an aspect ratio of 2:3).
The film is available in lengths for varying numbers of exposures. The standard full-length roll has always been 36 exposures (assuming a standard 24×36 frame size). Through about 1980, 20 exposure rolls were the only shorter length with widespread availability. Since then, 20 exposure rolls have been largely discontinued in favour of 24 and 12 exposure rolls.
|Photo by Bernard Rose|
120 is a popular film format for still photography introduced by Kodak for their Brownie No. 2 in 1901. It was originally intended for amateur photography but was later superseded in this role by 135 film. 120 film and its close relative, 220 film, survive to this day as the only medium format films that are readily available to both professionals and amateur enthusiasts.
The 120 format is a roll film, 60mm wide. The film is held in an open spool originally made of wood with metal flanges, later all metal, and finally plastic. The length of film is typically 30 inches (76 cm) up to 32–33 inches (81–84 cm), attached to a piece of backing paper longer and slightly wider than the film. The backing paper protects the film while it is wound on the spool, with enough extra length to allow loading and unloading the roll in daylight without exposing any of the film. Frame number markings for the three standard image formats (6×4.5, 6×6, and 6×9; see below) are printed on the backing paper.
The 220 format was introduced in 1965 and is the same width as 120 film, but with about double the length of film and thus twice the number of possible exposures per roll.
|Photo by DeGuilherme|
Instant film is a type of photographic film invented by Agfa, but first introduced by Polaroid to be used in an instant camera (and, with accessory hardware, with many professional film cameras). The film contains the chemicals needed for developing and fixing the photo, and the instant camera exposes and initiates the developing process after a photograph has been taken.
Instant film is available in sizes from 24 mm × 36 mm (similar to 135 film) up to 50.8 cm × 61 cm size, with the most popular film sizes for consumer snapshots being approximately 83mm × 108mm (the image itself is smaller as it is surrounded by a border). Early instant film was distributed on rolls, but later and current films are supplied in packs of 8 or 10 sheets, and single sheet films for use in large format cameras with a compatible back.
Instant positive film (which produced a print) uses diffusion transfer to move the dyes from the negative to the positive via a reagent. The process varies according to the film type.
In February 2008, Polaroid (under the control of Thomas J. Petters of Petters Group Worldwide) announced it would cease production of all instant film; the company will shut down three factories and lay off 450 workers. Sales of chemical film by all makers have dropped by at least 25% per year since 2000, but a new birth of interest around Fujifilm and in particular The Impossible Project's new films is seeing a rise in its popularity amongst creative artists.
Advanced Photo System (APS)
|Photo by Gemma White|
Advanced Photo System (APS) is a now discontinued film format for still photography first produced in 1996. It was marketed by Eastman Kodak under the brand name Advantix, by FujiFilm under the name Nexia, by AgfaPhoto under the name Futura and by Konica as Centuria.
The film is on a polyethylene naphthalate (PEN) base, and is housed in a single-spool 39 mm long plastic cartridge. The basic diameter is 21 mm, while it measures 30 mm at the slot where the film exits. The slot is protected by a lightproof door. It is available in 40, 25 and 15 exposure lengths.
(All information from Wikipedia, via Lomography)