Dancer, John Benjamin (1812-87), English photographer and inventor, who inherited his father's Liverpool instrument-making business aged 23. Dancer became a pioneer of photographic lantern slides. In 1837 he introduced the use of limelight as the source of illumination for magic lanterns, and later modified their optical arrangement, improving the quality of projected images. In 1840 he demonstrated the daguerreotype process at the Liverpool Mechanics' Institution, and exhibited a magnified image of a flea. In Manchester from 1841, he continued experimenting with photomicrography and microphotography and, following the introduction of the wet-plate process, perfected his method, exciting much enthusiasm from both the public and scientists. In 1853 he developed a twin-lens stereoscopic camera with the lenses set at what scientists considered the normal interocular distance of 6.35 cm (2½in). This innovation simplified the production of stereographs. As Dancer's eyesight deteriorated in the 1870s, two of his daughters took over the business of producing photomicrographs, before selling all the negatives to Richard Suter in 1896.
— Siobhan Davis
