Instant film Guide, Meaning , Facts, Information and Description
Instant film is a photographic film that is designed to be used in an instant camera. The film pack contains the chemicals needed for developing, and the instant camera automatically initiates the developing process after a photograph has been taken. In most types of Polaroid instant cameras, the film is pulled out through rollers which break open a pod containing the chemicals. The chemicals spread out over the surface of the film, and the positive image appears a few minutes later. Instant film is available in 24mm x 36mm size (similar to 135 film) up to 8" x 10" size, with the most popular film sizes for consumer snapshots being approximately 3¼" x 4¼" (the image itself is smaller as there is a border surrounding the image). Early instant film was distributed on rolls, but currently is typically distributed folded into film packs of 8-10 exposures that allow each image to be removed from the camera after it has exposed. Some modern film packs also contain a flat electrical battery to drive motors in the camera. This inclusion of the battery with the film ensures that a properly charged battery is always available for use.Instant film is frequently used in situations where it is necessary to validate soon after taking a photograph that the resulting image was suitable, such as in documenting evidence in law enforcement, in health care and scientific applications, and producing photographs for personal identification, such as for use in passports. Instant film is also used by artists to achieve effects that would be more difficult to accomplish with traditional photography, by manipulating the emulsion during the developing process, or separating the image emulsion from the film base.
Instant film is notable for having had a wider range of film speeds available than other negative films of the same era: instant film has been produced with ASA 4 to ASA 20,000. Current instant film formats typically have an ASA between 150 and 3000.
Besides Polaroid, Fuji also produce instant film. Kodak was prohibited in 1986 from further selling instant cameras and instant film.
An instant motion picture film, Polavision, was introduced by Polaroid in 1978, with an image format similar to Super 8mm film, and based on an additive color process. Polavision required a specific camera and tabletop viewer, and was not a commercial success, but did lead to the development of an instant 35mm color slide film.