D. Shackman & Sons were an English instrument manufacturer, who have made various special purpose cameras, such as passport cameras taking two or four copies of the same picture, oscilloscope cameras and automated cameras for sequences of pictures - and camera accessories such as interval timers. The company now seems to be called Shackman Instruments Ltd., based in Gerrard's Cross, Buckinghamshire. There are reports (on auction sites) of some of the passport cameras fitting both Polaroid and Fuji instant films.
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