Dark room

A darkroom is a workshop used by photographers working with photographic film to make prints and carry out other associated tasks. It is a room that can be made completely dark to allow the processing of the light sensitive photographic materials, including film and photographic paper. Various equipment is used in the darkroom, including an enlarger, baths containing chemicals, and running water.

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.

In most darkrooms, an enlarger, an optical apparatus similar to a slide projector, that projects the image of a negative onto a base, finely controls the focus, intensity and duration of light, is used for printmaking. A sheet of photographic paper is exposed to the enlarged image from the negative.

When making black-and-white prints, a safelight is commonly used to illuminate the work area. Since the majority of black-and-white papers are sensitive to only blue, or to blue and green light, a red- or amber-colored light can be safely used without exposing the paper.

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