GSK-99

From Camera-wiki.org
Jump to: navigation, search

The Type 99 Ultra Small Aerial Camera (GSK-99) entered service with the Imperial Japanese Army in 1940. It is the smallest of the aerial cameras produced. Unlike the standard Navy Type 99 and Army Type 100 models, the GSK-99 had interchangeable roll holder backs for 120 film that could be pre-loaded for ease of handling during flight. The camera has a wind up mechanism that triggered both film advance and cocked the shutter, allowing for rapid shooting of up to six images. In total, ten 6×6 images can be fit on a 120 roll of film. The GSK-99 film advance does not compensate for picture spacing. The first two frames may overlap if the film is not loaded correctly, and the spacing between the images will in-crease progressively.

       The protective camera case allowed for the camera and two pre-loaded roll holders, as well as filters and spare rolls of film. The roll holders had a white Bakelite plate affixed to the back that allowed the photographer to add notes (in pencil) to the images taken on the roll. The camera could be operated hand-held or, with the removal of the wooden handles, could be fit-ted to the aircraft frame and then operated with a remote release, thus generating overlapping frames suitable for 3D interpretation.[1]

       The camera had been designed and was mainly produced by Konishiroku with a small run of the unit built by Tōkyō Kōgaku. The Konishiroku-built GSK-99 was fitted with a fixed focus Rokuoh-sha Hexar Ser. II 75mm f/3.5 lens, set in a Compur-type Seikosha shutter, while the Tōkyō Kōgaku-built GSK-99 was equipped with a fixed focus Simlar 75mm f/3.5 lens,

       In total, about 2,500 to 3,000 units may have been built by Tōkyō Kōgaku and Konishiroku. Total annual production figures are unclear. While a report from the U.S. Naval Technical Mission to Japan, written in December 1945, gives detailed production figures for the Konishiroku built GSK-99 in the 1941–1945 period (Table 1),[2] figures for Tōkyō Kōgaku are sketchy. It seems that the latter company produced as few as 187 units in 1941, compared to 900 units supplied by Konishiroku.[3] Based on the observed serial numbers we can assume that at least 600 GSK-99 units were supplied by Tōkyō Kogaku.[4]

Table 1 Production volume of GSK-99 for the period 1941-1945[2][3]

        Years      
    1941 1942 1943 1944 1945 Total
Ordered 900 500 500 0 0
Konishiroku Delivered 900 477 0 361 144 1882
Ordered  ?  ?  ?  ?  ?
Tōkyō Kogaku Delivered 187  ?  ?  ?  ? ~600
TOTAL ~2500 (?)


       The two models are readily distinguishable by the nature and placement of the labels and the paint finish. From the limited number of cameras seen, it would appear that the Tōkyō Kōgaku model has a grey to brown crinkle paint finish with metal tags, while the Konishiroku model has a smooth paint finish (grey or dark green) with bakelite tags.


Notes

  1. Spencer, F (1946) Japanese Aircraft Cameras. Report FA278/3. Technical Note PH.381. Farnborough, Hants, UK: Royal Aircraft Establishment
  2. 2.0 2.1 Japanese Naval Photography. Compiled by Lt W.D.Hedden, USNR, with LtCdr G.Z.Dimitroff USNR and Lt(jg) W.A. Seymour, USNR. Intelligence Targets Japan (DNI) of 4 September 1945. Facicle A-1, Target A-39. U.S. Naval Technical Mission to Japan. December 1945. pp.8-9
  3. 3.0 3.1 陸軍 99式極小航空写真機 (Army 99 type minimum aeronautical camera) at Wetwing.
  4. Serial number info courtesy Prof. D Spennemann (Australia)
Personal tools
Namespaces

Variants
Actions
Navigation
External
Tools