microphotograph

1. A photograph requiring magnification for viewing.
2. A photograph on microfilm.
3. See photomicrograph.

Microphotography (or microimaging), the process of making microscopically small photographs of large objects by optical reduction. It became a popular means of creating photographic jewellery and novelties (e.g. stanhopes) in the 1860s, and a memorial ring incorporating a microphotograph of Prince Albert was made for Queen Victoria in 1861. The same method was used to create composite portraits of 500 or more celebrities on a single carte de visite (so-called ‘mosaic cards’), for viewing with a magnifying glass.

The technology was used during the Franco-Prussian War (1870-1) and First World War to produce tiny copies of messages to be carried by pigeons. Initially these were made through a reversed microscope system and read through a conventional microscope. ‘Microdot’ messages by espionage organizations hidden under full stops in other, innocent, messages were encoded and read by similar means. (Such a procedure had been suggested by Sir David Brewster in 1857; Japanese agents may have carried ingested micro-documents in the Russo-Japanese War (1904-5). ) An application of microimaging in the Second World War was the airgraph. Today, microimaging is a standard procedure in the semiconductor industry for producing masks for microcircuits.

— Graham Saxby

Bibliography

• Henisch, H. H. and B. A., The Photographic Experience 1839-1914: Images and Attitudes (1994)

1. A photograph requiring magnification for viewing.
2. See photomicrograph.

A photograph of small size.