Canon X-ray camera
Canon, while still named Seiki Kōgaku, made a 35mm camera for recording images on the fluorescent screen of an X-ray machine. This camera is quite simple, not needing some of the features of a camera for ordinary photography. It has no shutter; just a metal dark slide in a slot in the top plate (actual exposure would presumably be controlled by the time the x-ray source was exposed). It has knobs to advance and rewind the film. A short length of chain is wound around the advance knob, and through a metal guide at the front: this allows the film to be advanced (perhaps just one frame) by pulling a string attached to the chain: the operator would use the camera from behind a protective screen as far as possible, to avoid exposure to x-rays. The exposed frame is 25x26mm.
The camera forms part of a kit: two camera bodies, the lens, and some reusable film cassettes.[1] Both the camera body and the kit are very similar indeed to the 1950s Mamiya X-30, which was in fact supplied with Canon film cassettes for some of its time. It is possible that the design was shared. The lens for the camera is an R-Serenar 5cm f/1.5 in the example cited. This lens was made for this job, and has no iris diaphragm or focusing. The lens is mounted in a short cone-shaped cowl, which would fasten over the fluorescent screen. The camera body attaches to the rear of the lens with a wide bayonet fitting. Examples may be seen which have been converted to a 39mm thread-mount. Lenses for Seiki Kōgaku cameras were at first made by Nippon Kōgaku (Nikon),[2] and it is quite probable that there are X-ray camera kits with those lenses.
A US brochure from around 1956 (the Canon VT is the newest model shown) offers X-ray camera kits. Sadly the brochure only states For photographing X-ray images on the fluorescent screen, Canon makes two kits of X-ray camera.[3]
Notes
- ↑ X-ray camera kit sold by Christie's in May 2006: two camera bodies, serial no.s 2381 and 2382, with R-Serenar 5cm f/1.5 serial no.3092 in conical instrument cowl, and with two film cassettes, in outfit case. The auctioneer notes the camera is engraved (in Japanese) Seiki Optical Industry Co. Ltd. X-ray Indirect Photographing Device Army Noborito Laboratory. No 2 Section. No. 4 Group. and notes that the Noborito Laboratory operated in Kanagawa between November 1937 and August 1945. Japan was already at war with China (which was supported by the western Allies) since July 1937.
- ↑ 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). p177.
- ↑ Canon System of Photography brochure, about 1956, reproduced at Pacific Rim Camera. Oscilloscope, radar and X-ray cameras are discussed on p.31.
