APS film (Advanced Photo System)
1996 (launched by Kodak, Fujifilm, Canon, Minolta and Nikon)
A 24mm film in a drop-in cartridge, with three print shapes: H, C (classic) and P (panoramic). It faded quickly, but its 'C' frame gave its name to the APS-C digital sensor.
How it began
In 1996 five companies, Kodak, Fujifilm, Canon, Minolta and Nikon, launched the Advanced Photo System to win back amateurs with easier, smaller cameras. Kodak sold it as Advantix.
How it works
The film was 24mm wide, in a cartridge that the camera loaded and rewound by itself. A transparent magnetic layer recorded settings and the chosen print shape. Every frame was exposed at 30.2 × 16.7 mm, and the lab printed it as H (wide), C (classic 3:2, cropped to 25.1 × 16.7 mm) or P (panoramic).
Why it mattered
APS itself was a commercial disappointment, overtaken by digital within a few years. But early digital SLR sensors were about the size of its C frame, so the industry called them APS-C, a name that lasted long after the film. See formats and crop factor.
Limits and what replaced it
Its negatives were about 40% smaller than 35mm frames, so quality suffered in big enlargements, and digital compacts soon outdid it on convenience.
Today
The film is long gone, but 'APS-C' is the most common sensor size in interchangeable-lens cameras.