The Ohca is a Japanese 6.5×9cm plate folder made from 1935 by Rokuoh-sha, the manufacturing branch of Konishiroku.
The name which appears on at least some cameras is Ohca. It is spelled "Ohka" in various sources, either by mistake or because it appears as such on other examples. This name is usually written in katakana script (オーカ) in the original documents; at least one leaflet confirms that it comes from the word 桜花 in kanji script, meaning "cherry blossom". The name would later be used for the 1945 suicide plane, but this is the same oh character as that in Rokuoh-sha, and the company had long used both sakura (the other reading of the same character) and "cherry" to name its products.
The Ohca has a metal body, similar to that of the Idea (1933). It is easily distinguished by its focusing worm screw on the photographer's right. The bellows has true double extension. The distance scale is on the left of the focus rails, and there is sometimes a depth-of-field table on the camera's left side. There is brilliant finder atop the front standard, and a wireframe finder on the left. The camera has limited vertical movement ability. On at least some cameras, the name is inscribed as Ohca on an oval plate riveted inside the folding bed between the focus rails.
Lens and shutter
The Ohca was offered with either an Apus (T, B, 25–100) or a Durax (T, B, 1–125) dial-set shutter, and a Rokuoh-sha Optor Anastigmat 10.5cm lens in either f/6.3 or f/4.5 aperture. (Despite the Rokuoh-sha engraving on the lens rim, the Optor lenses were supplied by Asahi Kōgaku.) Surviving examples are confirmed with the Optor f/6.3 and the Apus or Durax. The depth-of-field table on the side has the lens name Optor Anas't 10.5c.m and the word 焦点震度表 (meaning "depth-of-field table").
Examples are also known with a Durax shutter and a Rodenstock-Trinar-Anastigmat f/4.5 lens, and perhaps no depth-of-field table. The markings on the lens rim do not display the focal length but 2¼×3¼ instead, indicating the intended format in inches.
The Ohca was advertised from November 1935 and was featured in the December 1935 issue of Asahi Camera. Advertisements dated December 1935, September 1936 and February 1937 all give the same prices of ¥32 with an f/6.3 lens and ¥37 with an f/4.5. The last reported advertisement is in Asahi Camera May 1939; it gives the prices as ¥47 with an f/6.3 lens and ¥52 with an f/4.5, both with a Durax shutter. This advertisement also says that brown or green leather covering was available for ¥2 extra. The official list of set prices compiled in October 1940 and published in January 1941 still has an Ohca I (¥43), Ohca II (¥52) and Ohca III (¥54), with no further detail.
- ↑ See e.g. Sugiyama, items 1149–50, or McKeown, p.543.
- ↑ Leaflet reproduced in this page of the R. Konishi Rokuoh-sha website.
- ↑ Kokusan kamera no rekishi, p.334.
- ↑ Apus, Optor f/6.3: example pictured in Sugiyama, item 1149, and example observed in an online auction. Durax, Optor f/6.3: example pictured in Tanaka, p.41 of Kurashikku Kamera Senka no.10.
- ↑ Example pictured in Sugiyama, item 1150, and in Kamera no ayumi, p.84, belonging to the Pentax Gallery and showing no depth-of-field table, and example pictured in this page at Asacame.
- ↑ Kokusan kamera no rekishi, p.334.
- ↑ Advertisement in Photo Times December 1935 reproduced in Kokusan kamera no rekishi, p.82. Advertisement in Asahi Camera September 1936 reproduced in the same, p.60. Advertisement in Kogata Camera February 1937 reproduced in the same, p.82.
- ↑ Advertisement reproduced in Kokusan kamera no rekishi, p.82. It is the last advertisement listed in this source, p.334.
- ↑ "Kokusan shashinki no kōtei kakaku", type 8, sections 1, 2 and 4A.
- 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. Item 31. (See also the advertisements for items 167 and 170–1.)
- Kamera no ayumi. Zen nihon shashin renmei sōritsu 50-shūnen kinen (カメラのあゆみ・全日本写真連盟創立五〇周年記念, History of cameras, commemorating the 50th anniversary of the All Japan Association of Photographic Societies). Tokyo: Asahi Shinbunsha, 1976. No ISBN number. P.84.
- "Kokusan shashinki no kōtei kakaku" (国産写真機の公定価格, Set prices of the Japanese cameras), listing Japanese camera production as of October 25, 1940 and setting the retail prices from December 10, 1940. Published in Asahi Camera January 1941 and reproduced in 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. Pp.108—9. Type 8, sections 1, 2 and 4A.
- 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.182 (about the Optor lenses only).
- 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.543.
- 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. Item 1149–50.
- Tanaka Masao (田中政雄). "Konica history 5. Shōwa 8-nen – 20-nen." (Konica history 5. 昭和8年–20年. From Shōwa year 8 (1933) to Shōwa year 20 (1945).) 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.10, September 1987. No ISBN number. Konishiroku kamera no rekishi (小西六カメラの歴史, special issue on Konishiroku). Pp.40–4.
- Ohca at Asacame
- Pages of the R. Konishi Rokuoh-sha website:
- Ohca, including the reproduction of an original leaflet (click to enlarge)
- Ohca in the camera list
|Konishiroku prewar and wartime cameras ( )|
|plate||hand cameras||stereo hand cameras||strut folders||box||telephoto||SLR|
|Idea (original) | Idea A | Idea B | Idea Snap | Idea No.1 | Idea (metal) | Lily (original) | Lily (horizontal) | Lily (metal) | Tropical Lily | Noble | Ohca | Sakura Palace | Sakura Pocket Prano | Sakura Prano||Idea Binocular | Sakura Binocular Prano||Minimum Idea | Idea Spring | Korok||Champion | Cherry | Sakura Army | Sakura Honor | Sakura Navy||Idea Telephoto||Idea Reflex (1910 and 1911) | Idea Reflex (1932) | Neat Reflex | Sakura Reflex Prano|
|rollfilm||folders||box or collapsible||TLR|
|Pearlette | Special Pearlette | B Pearlette | Pearl (for plates and rollfilm) | Pearl No.2 | Pearl (Year 8) | Baby Pearl | Semi Pearl | Sakura Palace||Record | Sakura (box) | Sakura (bakelite)||Sakura-flex|