The Advanced Photo System was an attempt of a major upgrade of photographic technology for amateurs, but was soon overtaken by the popularity of digital photography. Despite the added features, APS never really caught on with professional photographers because of the significantly smaller film area (56% of 135 film). Color slide film, popular with professional photographers, proved unpopular in APS format and was soon discontinued (although chromogenic black-and-white IX240 film continued to be produced). Color print film was normally available only in a limited selection of film speeds and color formats. These developments, combined with the fact that auto-loading 35mm cameras could be made almost as compact, as convenient, and as inexpensive as APS-format cameras, prevented APS from attaining greater popularity.