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Description: | 'C' Type vertical aerial camera with plate changer mechanism, showing the spring tension adjustment. At lower right is a stack of unexposed 5" x 4" glass plates in their light-proof envelopes.
This camera consisted of the A' Type body and shutter mechanism, fitted with a semi-automatic plate-changing apparatus in place of the Mackenzie-Wishart slide system. Lenses from 8 up to 17 focal length could be fitted.
A wooden magazine on top of the camera held 18 unexposed 5" x 4" plates in metal sheaths, stacked face down over the exposure aperture and falling into position as required. An operating handle on a platform to one side of this magazine was pushed forward to set the shutter: the handle was then returned to its original position and the shutter released by means of a cord attached to a trigger on the side of the body. After exposure, the action with the operating handle was repeated, resetting the shutter, sliding the exposed plate over and into a receiving magazine attached in an inverted position under an extension on the other side of the camera, and allowing the next unexposed plate to drop down over the aperture. This system enabled an overlapping series of photographs be made. To prevent the plates from accidental exposure during the shutter-setting operation, a metal masking plate was automatically placed between the lens and the plates. On later models, a self-capping focal plane shutter consisting of two vertically travelling cloth blinds with a choice of speeds from 1/250th to 1/500th of a second. was fitted. The C' Type weighed 26 lbs.
Because the plate-changing system was gravity-fed, the C' Type, - and the successive E', L' and LB' Types which were fitted with similar apparatus, - could only be operated in a fixed mounting in the vertical position. | Publisher: | http://www.iwm.org.uk | Source: | Imperial War Museum | Creator: | Thornton Pickard Ltd. | Identifier: | http://www.iwm.org.uk/collections/item/o... | Go to resource |
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