The no-need-darkroom process was used by many inexpensive Japanese cameras from the late 1920s to the postwar period. It was notably used by Tougodo from 1930.
The film was sold in light-proof paper sheaths, with a sliding paper cover. The sheath was loaded into the camera, and the paper cover was slid out to take the picture, then put back before unloading the camera. After the exposure, the sheath was immersed in red-tinted developer fluid and opened again. Complete darkness was not required, because the developer fluid contained a desensitizing agent. This was perhaps phenosafranine or basic scarlet N (a mix of phenosafranine and chrysoidine), red-coloured dyes which were used for that purpose at the time. The film was then immersed in the fixer, removed from the sheath and washed, and the negative was ready. It was usually turned into contact prints, which could be processed in the same chemicals, again in daylight. Printing paper was available for natural light or for electric light, that for natural light usually costing more.
Sellers of Tougo cameras used to demonstrate the process in the street corners in front of their shops, washing the negative with ether and using an electric fan to speed up the washing and drying steps. The resulting picture was offered to the clients, who only had to wash it at home for two hours.
- Article by Yoshikawa Hayao in Asahi Camera May 1931, reproduced in Awano, pp.16–8 of Camera Collectors' News no.316. It does mention the use of a dye as a desensitizing agent, but only says that it is a "scarlet dye, cheaper than the pinacryptol green generally used" for that purpose (at the bottom of p.17). Awano, p.10 of the same magazine, briefly comments on this. Chū, p.25 of Camera Collectors' News no.47, also mentions a desensitizing agent, but his account is unclear, and perhaps based on an erroneous interpretation of Yoshikawa's article. Sugiyama, p.63, says that the "red developing fluid protects the red-insensitive film from incoming light", but this is an incomplete explanation.
- See for example this thread at graflex.org. Basic scarlet N was discovered around 1925 according to the preface of The British Journal Photographic Almanac 1926.
- Shirai, p.144 of Asahi Camera June 1955: これを速く乾かすためにはエーテルにさっと入れ扇風機の前に置けばいい.
- Shirai, p.144 of Asahi Camera June 1955: お宅へ帰って二時間水洗いして下さい.
- Awano Mikio (粟野幹男). "Tougō kamera (3)" (トウゴーカメラ, Tougo cameras ). In Camera Collectors' News no.316 (October 2003). Nishinomiya: Camera Collectors News-sha. Pp.9–21. Contains a reproduction of the user manual of the Baby, explaining the process, and a reproduction of an article by Yoshikawa Hayao (吉川速男) in Asahi Camera May 1931.
- H.M. Kanpo (H・M・カンポ). "Omocha-bako (1)" (おもちゃ箱 , Toy box ). In Camera Collectors' News no.51 (September 1981). Nishinomiya: Camera Collectors News-sha. Pp.23–4. (Memories of a person who bought a Tougo box camera from a demonstration stand when he was a child.)
- Lewis, Gordon, ed. The History of the Japanese Camera. Rochester, N.Y.: George Eastman House, International Museum of Photography & Film, 1991. ISBN 0-935398-17-1 (paper), 0-935398-16-3 (hard). P.43.
- McKeown, James M. and Joan C. McKeown's Price Guide to Antique and Classic Cameras, 12th Edition, 2005-2006. USA, Centennial Photo Service, 2004. ISBN 0-931838-40-1 (hardcover). ISBN 0-931838-41-X (softcover). P.931.
- Naka Kazunori (中一訓). "Shashin Zuisō: Tōgō kamera" (写真随想・トーゴーカメラ, Photographic thoughts: Tougo cameras). In Camera Collectors' News no.47 (May 1981). Nishinomiya: Camera Collectors News-sha. Pp.25–6. (Brief explanation of the no-need-darkroom process and Tougo cameras).
- Schulz, Alexander. "Kameras aus dem Hause Tougo (I)" (Cameras of the Tougo firm [I]). In Photographica Cabinett no.42 (2007). Pp.16–21.
- Shirai. "Tōgō kamera: 'En-kame' yume miru san-kyōdai" (東郷カメラ・"円カメ"夢みる三兄弟, Tougo cameras: three brothers who dreamed of "yen-cameras"). In Asahi Camera June 1955. Pp.144–5.
- Sugiyama, Kōichi (杉山浩一); Naoi, Hiroaki (直井浩明); Bullock, John R. The Collector's Guide to Japanese Cameras. 国産カメラ図鑑 (Kokusan kamera zukan). Tokyo: Asahi Sonorama, 1985. ISBN 4-257-03187-5. P.63.