A darkroom is a room that can be made completely dark to allow the processing of light sensitive photographic materials, including photographic film and photographic paper. Darkrooms have been created and used since the inception of photography in the early 19th century. Darkrooms have many various manifestations, from the elaborate space used by Ansel Adams to a retooled ambulance wagon used by Timothy H. O'Sullivan. From the initial development to the creation of prints, the darkroom process allows complete control over the medium.
Due to the popularity of color photography and complexity of processing color film (see C-41 process) and printing color photographs and also to the rise, first of Polaroid technology and later digital photography, darkrooms are decreasing in popularity, though are still commonplace on college campuses, schools and in the studios of many professional photographers.
Other applications of darkrooms include the use in nondestructive testing, such as magnetic particle inspection.
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