Advanced Photo System

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 Agfa under the name Futura and by Konica as Centuria.

The film is 24 mm wide, and has three image formats:

The "C" and "P" formats are formed by cropping. The full image is recorded on the film, and an image recorded in one aspect ratio can be reprinted in another. The "C" format has an equivalent aspect ratio to a 135 film image. Most APS cameras (with the exception of some disposable cameras) can record all three formats; the format selection is indicated on the film by a series of exposed squares alongside the image area or recorded on the magnetic coating depending on the camera. In the absence of an operator-specified format, the machine printing an APS roll will use these indicators to determine the output format of each print.

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. The film surface has a transparent magnetic coating, and the camera uses this information exchange (IX) system for recording information about each exposure. The camera handles winding and rewinding automatically, to the extent that partially exposed films can, in certain cameras, be removed and used later. Numbered symbols (called 'visual indicators') on the cartridge end indicate the status:

Additionally, a tab on this end of the cartridge indicates that the cartridge has been processed.

A major distinction of APS film was the ability to record information other than the image. This information exchange was most commonly used for print aspect ratio, but could also be used to record the date and time that the photograph was taken, store a caption, and record exposure data such as shutter speed and aperture setting. This information could be read by the photo printing equipment to determine the print aspect ratio, print information on the back (or, rarely, the front) of the photograph, or to improve print quality.

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