Okada and Daiichi
Okada Kōgaku, later Daiichi Kōgaku, then Zenobia Kōgaku was a Japanese camera maker based in Tokyo.
Okada Kōgaku Seiki K.K. (岡田光学精機株式会社) was perhaps already active in the mid-1930s: many sources say that it made the original Walz 3×4 camera in 1936–7, attributed to "Walz Camera Works" in original advertisements. From 1940, the company made the Okaco and Waltax 4.5×6 folders. The Kolex lens and Dabit-Super shutter mounted on these cameras were made by the company itself, which was also making binoculars. The company name was often abbreviated to Okako (岡光, Okakō, from Okada Kōgaku), and the cameras have an OKAKO TOKYO logo. In 1943, the address was Toshima-ku Nishisugamo-chō 4–276 (東京都豊島区西巣鴨町4–276).
From Okada to Daiichi
The company survived the war and continued the Waltax series. In 1948 it was still called Okada Kōgaku Seiki K.K., and its address was Kita-ku Shimo-Jūjōmachi 1894 (東京都北区下十條町一八九四). Around 1949–50, it was using the name Okada Optical Industrial Co., Ltd. on documents in English language. The address changed around that time, to Itabashi-ku Shimura-Maeno-chō 1045 (東京都板橋区志村前野町1045), and remained there at least until 1954. In 1949—50, Okada made various subminiature cameras developed by the engineer Ishiwata Shigeo (石渡茂雄): the Hit-type Kolt, the pistol-shaped Gemmy, and the Camera "A" and Camera "B" made on request of the US military.
Around 1951, the company changed its name to Daiichi Kōgaku K.K. (第一光学株式会社) — a document dated December 1951 seems to imply that the name change was fairly recent. After the change of the company name, a few Waltax cameras were made with a new shutter renamed D.O.C.-Rapid — the initials certainly stand for Daiichi Optical Company, a translation of Daiichi Kōgaku K.K.
The Waltax was renamed Zenobia in early 1952, with almost no change in the features, and the Bio-Kolex lens became the Hesper. The reason for the near simultaneous change of the company name and of the brand names of the camera, lens and shutter is unknown. The Zenobiaflex 6×6 TLR was introduced in 1953. The D.O.C.-Rapid leaf shutter was upgraded and renamed Daiichi-Rapid around 1953, and the Hesper lens was recomputed as the Neo-Hesper around 1954.
Financial problems and labour conflict
In 1954, the company was producing 3,000 cameras per month and had 450 employees, but it did not anticipate the sudden loss of popularity of the folding cameras and the switch of the market towards 35mm cameras. In May, the announcement that 125 people would be laid off caused conflicts with the trade unions. A lockout was declared in June during ten days, and the workers reacted by occupying the factory and organizing the production themselves. The conflict ended at the end of June, but the company had unpaid notes which caused a suspension of banking transactions. Production remained stopped for two months, resuming in late August, and 200 people voluntarily retired. The financial situation of the company was still bad, and in March 1955 the factory was closed and all the remaining workers were dismissed.
Before its failure, the company made a preseries of Leica copies called Ichicon-35, perhaps originally designed by Kumagai Genji. The camera was finally released in mid 1956 by Mejiro Kōgaku as the Honor S1.
Reorganized as Zenobia
The company was reorganized as Zenobia Kōgaku K.K. (ゼノビア光学株式会社) in February 1956, adopting the brand name of the cameras. The address was initially the same as used by Daiichi, then it became Itabashi-ku Azusawa 2, 4 (東京都板橋区小豆沢２の４) in 1957–8. The company sold some late Zenobia and Zenobiaflex models, then developed the Zenobia 35 fixed-lens rangefinder and remained in existence until late 1958.
- Walz (3×4cm strut folder)
- Ichicon-35 (Leica copy, c.1954—5), some examples were perhaps called "Zenobia 35"
- Zenobia 35 (rangefinder camera with leaf shutter, 1957—8)
- Kolt (17.5mm film)
- Gemmy (16mm film)
- Camera "A" (8mm film)
- Camera "B" (16mm film)
- unknown 16mm stereo camera (unconfirmed, see Camera "A" and Camera "B")
- E. Hesper 50mm f/3.5 enlarging lens (four elements, click-stop diaphragm)
- Dabit filters (Okada period)
- Full name: prospect pictured here at the AJCC, and "Kokusan shashinki no genjōchōsa" ("Inquiry into Japanese cameras").
- Kokusan kamera no rekishi, p.344 (item 346); Sugiyama, item 1262; McKeown, p.745.
- Lens and shutter made by the company: "Kokusan shashinki no genjōchōsa" ("Inquiry into Japanese cameras"), lens items La1 and Lb34 and shutter item 18-R-2. Binoculars: wartime advertisement reproduced in Nostalgic Camera by Toshio Inamura.
- "Kokusan shashinki no genjōchōsa" ("Inquiry into Japanese cameras").
- English user manual for the Kolt, observed in an online auction.
- Source: English user manual for the Kolt, observed in an online auction, advertisement on p.11 of the supplement to the December 1951 issue of Photo Art, and advertisements dated April 1952 to April 1954 reproduced in Kokusan kamera no rekishi, p.144.
- Yazawa, p.11 of Camera Collectors' News no.233.
- Supplement to the December 1951 issue of Photo Art, p.11.
- Many sources attribute all the postwar Waltax to Daiichi Kōgaku but they are wrong: Sugiyama, items 1430–2, Kokusan kamera no rekishi, p.375 (items 1062–8), McKeown, p.239. Lewis, pp.61 and 75, attributes the Waltax II to Okada and the Waltax Senior to "Okada, later Daiichi".
- 3,000 cameras per month, 450 employees: extract of the Labour Year Book of Japan 1956, published in November 1955.
- All details: extract of the Labour Year Book of Japan 1956, published in November 1955.
- Date: Awano, p.2 of Camera Collectors' News no.35 and p.56 of Kurashikku Kamera Senka no.37.
- Advertisements dated June 1956 to January 1958, reproduced in Kokusan kamera no rekishi, p.252.
- The last advertisements and articles listed in Kokusan kamera no rekishi, p.389, are dated November 1958.
- Advertisement dated 1954 reproduced at the Shashin-Bako website
- Set of five 32mm filters observed in an online auction.
- Asahi Camera (アサヒカメラ) editorial staff. Shōwa 10–40nen kōkoku ni miru kokusan kamera no rekishi (昭和10–40年広告にみる国産カメラの歴史, Japanese camera history as seen in advertisements, 1935–1965). Tokyo: Asahi Shinbunsha, 1994. ISBN 4-02-330312-7.
- Awano Mikio (粟野幹男). "Kokusan Barunakku-gata kamera: Ōnā, Ichikon" (国産バルナック型カメラ・オーナー、イチコン, Japanese Leica-type cameras: Honor, Ichicon). In Kamera Rebyū: Kurashikku Kamera Senka (カメラレビュー クラシックカメラ専科) / Camera Review: All about Historical Cameras no.37, March 1996. No ISBN number. Leica Book '96 (ライカブック'96). Pp.56–7. (On the reorganization as Zenobia Kōgaku.)
- Awano Mikio (粟野幹男). "Ōnā 35 S1" (オーナー35S1, Honor 35 S1). In Camera Collectors' News no.35 (May 1980). Nishinomiya: Camera Collectors News-sha. (On the reorganization as Zenobia Kōgaku.)
- HPR. Leica Copies. London: Classic Collection Publications, 1994. ISBN 1-874485-05-4.
- "Kokusan shashinki no genjōchōsa" (国産写真機ノ現状調査, Inquiry into Japanese cameras), listing Japanese camera production as of April 1943. Reproduced in Supuringu kamera de ikou: Zen 69 kishu no shōkai to tsukaikata (スプリングカメラでいこう: 全69機種の紹介と使い方, Let's try spring cameras: Presentation and use of 69 machines). Tokyo: Shashinkogyo Syuppan-sha, 2004. ISBN 4-87956-072-3. Pp.180–7.
- 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).
- 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).
- Nihon rōdō nenkan (日本労働年鑑, Labour Year Book of Japan) Vol.28, 1956. Ohara Institute for Social Research, 20 Nov. 1955. Extract about Daiichi Kōgaku in the OISR website.
- Photo Art 12-gatsu-gō furoku Saishin Kokusan Shashinki Sō-katarogu (フォトアート12月號附録最新国産写真機総カタログ, General catalogue of the latest Japanese cameras, supplement to the December issue). December 1951. P.11.
- 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.
- Yazawa Seiichirō (矢沢征一郎). "Renzu no hanashi (143) Kamera 'A'" (レンズの話カメラ'A', Lens story  Camera 'A'). In Camera Collectors' News no.233 (November 1996). Nishinomiya: Camera Collectors News-sha. Pp.11–5.
- Original Waltax and early prospects showing the full company name, in the AJCC website
- Advertisement for the Semi Okaco camera and Okako binoculars dated 1942 or later, reproduced in Nostalgic Camera by Toshio Inamura
- Advertisement for the Zenobia, Zenobiaflex and E. Hesper lens, published in 1954, reproduced in a page of Japanese postwar advertisements at the Shashin-Bako website