Editing 135 film (section)

=== Reflex cameras ===
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[[file:Nikon F SLR camera with NIKKOR-S Auto 1,4 f=5,8cm.JPG|thumb|[[Nikon F]] chrome with eyelevel prism and NIKKOR-S Auto 1:1,4 f=5,8cm lens (1959) – an early SLR [[system camera]]]]

Reflex viewfinders, both twin-and [[Single-lens reflex camera|single-lens]], had been used with earlier cameras using plates and rollfilm.

The first 35&nbsp;mm single-lens reflex (SLR) was the [[Kine Exakta]], introduced in 1936. [[World War II]] interrupted development of the type. After the war, Exakta resumed development and the Contax S model with the now familiar [[pentaprism]] viewing feature was introduced in 1949. In the 1950s, the SLR also began to be produced in Japan by such companies as [[Pentax|Asahi]] and [[Miranda Camera Company|Miranda]]. Asahi's Pentax introduced the [[instant-return mirror]], important for the popularity of SLRs; until then, the viewfinder on an SLR camera blanked as the mirror sprang out of the optical path just before taking the picture, returning when the film was wound on. [[Nikon]]'s [[Nikon F|F]] model, introduced in March 1959, was a [[system camera]] that greatly improved the quality and utility of 35&nbsp;mm format cameras, encouraging professionals (especially photojournalists) to switch from larger format cameras to the versatile, rugged, and fast SLR design. Numerous other film formats waxed and waned in popularity, but by the 1970s, interchangeable-lens SLR cameras and smaller rangefinders, from expensive Leicas to "point-and-shoot" pocket cameras, were all using 35&nbsp;mm film, and manufacturers had proliferated.

Colour films improved, both for print negatives and reversal slides, while black-and-white films offered smoother grain and faster speeds than previously available. Since 35&nbsp;mm was preferred by both amateur and professional photographers, makers of film stock have long offered the widest range of different film speeds and types in the format. The [[DX encoding|DX film-speed encoding system]] was introduced in the 1980s, as were single-use cameras pre-loaded with 35&nbsp;mm film and using plastic lenses of reasonable enough quality to produce acceptable snapshots. Automated all-in-one processing and printing machines made 35&nbsp;mm developing easier and less expensive, so that quality colour prints became available not only from photographic specialty stores, but also from supermarkets, drugstores, and [[Big-box store|big box]] retailers, often in less than an hour.