Editing Advanced Photo System (section)

=== Information exchange (IX) ===

A major distinction of APS film is the ability to record information other than the image. This [[metadata]] information is most commonly used for print aspect ratio, but can also be used to record the date and time that the photograph was taken, store a caption, and record [[exposure (photography)|exposure]] data such as [[shutter speed]] and [[aperture]] setting. This information can 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. The system was invented by four engineers at Kodak, who were awarded patents in 1992 and 1993 and who jointly were named the National Inventor of the Year in 1996.<ref>{{cite press release |url=http://www.kodak.com/aboutKodak/corpInfo/pressReleases/pr19960515-01.shtml |title=Engineers Named National Inventors of the Year For Their Contributions To Kodak's Advanced Photo System |date=May 15, 1996 |publisher=Eastman Kodak Company |archive-url=https://web.archive.org/web/19970319232828/http://www.kodak.com/aboutKodak/corpInfo/pressReleases/pr19960515-01.shtml |archive-date=March 19, 1997 |url-status=dead}}</ref>

Two methods for storing information on the film are employed: "magnetic IX" and "optical IX". Optical IX is employed by less expensive cameras and disposable cameras, and employs a light source to expose a small section of the film, outside of the image negative area. This method is limited to determining the print aspect ratio of the finished print.<ref name=PopPhoto-9603/>{{rp|34}}

Magnetic IX is used in the more expensive cameras and allows for more information exchange. Most cameras with magnetic IX automatically record the exposure date and time on tracks in the magnetic layer, outside the visible area, with more advanced models allowing the user to specify a predetermined caption to be printed on the photo or record the exposure settings, as well as determine print aspect ratio.<ref name=PopPhoto-9603/>{{rp|34}} Kodak claimed that a 40-exposure roll could record more than 80&nbsp;KB of data.<ref>{{cite web |url=http://www.kodak.com/ciHome/APS/apsMagnetics.shtml |title=Magnetics |archive-url=https://web.archive.org/web/19970122052958/http://www.kodak.com/ciHome/APS/apsMagnetics.shtml |archive-date=January 22, 1997 |publisher=Eastman Kodak Company |url-status=dead}}</ref> Magnetic IX reportedly caused some problems for photo processors, who found their magnetic reading heads had to be cleaned frequently, or that their equipment's ability to print this information was limited, but Kodak's testing indicated magnetic deposits were not a concern.<ref name=Kodak-FAQ/>