Editing 135 film (section)

=== Pre-loaded cassettes and Kodak Retina cameras ===
{{More citations needed|date=March 2014}}
[[file:Retina-II.jpg|thumb|Kodak Retina II]]

In the earliest days, the photographer had to load the film into reusable cassettes and, at least for some cameras, cut the film leader. In 1934, Kodak introduced a ''135'' daylight-loading single-use cassette. This cassette was engineered so that it could be used in both Leica and [[Carl Zeiss AG|Zeiss Ikon]] [[Contax]] cameras along with the camera for which it was invented, namely the [[Kodak Retina]] camera. The Retina camera and this daylight loading cassette were the invention of Dr. August Nagel of the ''Kodak AG Dr. Nagel Werk'' in Stuttgart. Kodak bought Dr. August Nagel's company in December, 1931, and began marketing the ''Kodak Retina'' in the summer of 1934.<ref>{{Cite web |title=Kodak Retina (Type 117) {{!}} Science Museum Group Collection |url=https://collection.sciencemuseumgroup.org.uk/objects/co8205056/kodak-retina-type-117 |access-date=2025-03-02 |website=collection.sciencemuseumgroup.org.uk |language=en}}</ref> The first Kodak Retina camera was a Typ 117. The 35&nbsp;mm Kodak Retina camera line remained in production until 1969. Kodak also introduced a line of American made cameras that were simpler and more economical than the Retina. [[Argus (camera company)|Argus]], too, made a long-lived range of 35&nbsp;mm cameras; notably the [[Argus C3]]. Kodak launched 135-format [[Kodachrome]] colour film in 1936. [[Agfa-Gevaert|AGFA]] followed with the introduction of ''Agfacolor Neu'' later in the same year.

The designations ''235'' and ''435'' refer to 35&nbsp;mm film in daylight-loading spools, that could be loaded into Contax or Leica style reusable cassettes, respectively,<ref>{{Cite web |title=A Brief History of Kodak Roll Film Numbers |url=http://www.luk.staff.ugm.ac.id/fotografi/off/www.rit.edu/andpph/tphs-filmnumbers.html |archive-url=https://web.archive.org/web/20230622050846/http://www.luk.staff.ugm.ac.id/fotografi/off/www.rit.edu/andpph/tphs-filmnumbers.html |archive-date=2023-06-22 |access-date=2021-09-19 |website=www.luk.staff.ugm.ac.id}}</ref> without need of a [[darkroom]]. The ''335'' was a daylight loading spool for the 24 × 23&nbsp;mm stereo format.