Spirit photography

Spirit photography is a type of photography whose primary attempt is to capture images of ghosts and other spiritual entities, especially in ghost hunting and has a strong history dating back to the late 19th century.

Spirit photography was first used by William H. Mumler in the 1860s. Mumler discovered the technique by accident, after he discovered a second person in a photograph he took of himself, which he found was actually a double exposure. Seeing there was a market for it, Mumler started working as a medium, taking people's pictures and doctoring the negatives to add lost loved ones into them (mostly using other photographs as basis). Mumler's fraud was discovered after he put identifiable living Boston residents in the photos as spirits.

Other spirit photographers also started to sell photographs. A later spirit photographer was Fred A. Hudson, who took many spirit photographs for spiritualists in 1872. Through the 1880s into the early 20th century spirit photography remained popular, with notable proponents such as Arthur Conan Doyle and William Crookes.William Stainton Moses, another spiritualist, claimed that spirit photography operated by means of a fluid substance called ectoplasm, in which the spirits take form. Some spiritualists authored books supporting spirit photography. Georgiana Houghton wrote Chronicles of the Photographs of Spiritual Beings and Phenomena Invisible to the Material Eye (1892) and James Coates wrote Photographing the Invisible (1911).

One of the later spirit photographers was William Hope (1863–1933). The psychical researcher Harry Price revealed that the photographs of Hope were frauds. Price secretly marked Hope's photographic plates, and provided him with a packet of additional plates that had been covertly etched with the brand image of the Imperial Dry Plate Co. Ltd. in the knowledge that the logo would be transferred to any images created with them. Unaware that Price had tampered with his supplies, Hope then attempted to produce a number of Spirit photographs. Although Hope produced several images of spirits, none of his materials contained the Imperial Dry Plate Co. Ltd logo, or the marks that Price had put on Hope's original equipment, showing that he had exchanged prepared materials containing fake spirit images for the provided materials.

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