Doryu 2-16 gun cam
This is a really great gun cam idea from 50's Japan. The Doryu 2-16 pistol camera were developed for police and surveillance tasks, mainly to catch photographic proof of criminal behaviour in the act. Despite what is said in some sources, none of these cameras was designed for shooting training. The Japanese police also felt the need for a camera specially designed to photograph protesters during demonstrations, the "bloody May Day incident" a clash between Tokyo protesters and policemen on May Day 1952.
The first Doryu camera was the Doryu 1, taking 9.5mm film, which was completed in 1952 and was rapidly abandoned due to durability problems, and because of the low availability of the film stock. The company immediately began to develop its successor the Doryu 2-16, taking 16mm film, which was completed in July 1954. By which time, the police force had already selected the Mamiya Pistol, made to the same specifications and supplied just in time for May Day 1954, and they rejected the Doryu. The camera was nonetheless produced for the civilian market, The camera internals were heavily modified before entering actual production: the number of parts (excluding the lens and shutter) was cut from 232 on the first prototype to 93 on the production version. This move improved the durability and reliability and contributed to cutting costs. It is said that the camera parts were of very poor quality. One author, who seems to have actually tried the camera, says that "the shutter is poor, the film flatness was not good and there were light leaks and the lens quality is bad". To be fair, the film flatness issue was probably caused by mproper use of Mamiya cassettes loaded with the emulsion inwards, giving a more contorted film path. These faults certainly explain the failure to meet the police specifications. The only advantage of the Doryu was arguably its built-in flash system, allowing to take pictures at night. But the absence of synchronisation, making flash exposures possible in B setting only, detracts much from its usability, and the bursting magnesium cartridges were certainly very dangerous for the user, making the camera a complete failure. Probably the coolest aspect of the Doryu was the fact that 6 magnesium cartridges were loaded in a pistol magazine and the catridges looked like real bullets. The cartridges are made of 0.1mm aluminium, rendered waterproof by 8/1000mm tinfoil and liquid vinyl. Each cartridge contains 0.8 gram of magnesium powder ignited by a paper strip impregnated with gunpowder, as was used at the time in toy guns.
The trigger both trips the shutter and fires the magnesium cartridge. It is locked by a lever on the left, next to the handgrip. Its movement is relayed to the flash cartridge by a sear, hammer and firing pin, exactly reproducing the mechanism of an actual firearm. When the cartridge is fired, burning magnesium powder is ejected through the aperture at the top, illuminating the scene up to a distance of 15m outdoors, and 20m indoors. The temperature is extremely high, and there is a risk of severe burning if the cartridge is fired at your hand or face. The flash duration is about 1/25 second, and varies with weather factors. The shutter is not synchronised, and the flash system can be used the B setting only. Known lenses made for the Doryu 2-16 are a Polymar 17/2.7 standard lens focusing to 25cm and a 15/2.2 "wide-angle" lens focusing to 15cm. The 15mm lens gives a very limited wide-angle effect, deemed useful to catch the subject with little aiming effort. But some sources mention a total of three lenses: 15/2.2, 17/2.5 and 17/2.7, named "Doryu" (ドリュー) or "Dorymar" (ドリマー), these names might be inaccurate. The surviving examples are usually found with a Hokutar 17/2.7, Dorymar 17/2.5 or Dorymar Wide Angle 15/2.2. The lens number patterns are not fully understood: it seems that the Hokutar is numbered in the 1xxx range, the Dorymar 17/2.5 in the D25xxx range, and the Dorymar Wide Angle 15/2.2 in the 522xxx range. At least one camera has been sold with a Dol Fixed Iris 30/5.6 lens.
