Editing Photography (section)

=== Color ===
{{Main|Color photography}}
[[File:Tartan Ribbon.jpg|thumb|The first [[color photograph]] made by the three-color method suggested by [[James Clerk Maxwell]] in 1855, taken in 1861 by [[Thomas Sutton (photographer)|Thomas Sutton]]. The subject is a colored, [[tartan]] patterned ribbon.]]
[[Color photography]] was explored beginning in the 1840s. Early experiments in color required extremely long exposures (hours or days for camera images) and could not "fix" the photograph to prevent the color from quickly fading when exposed to white light.

The first permanent color photograph was taken in 1861 using the three-color-separation principle first published by Scottish physicist [[James Clerk Maxwell]] in 1855.<ref name="King's College">{{cite news
| title        = 1861: James Clerk Maxwell's greatest year
| url          = https://www.kcl.ac.uk/newsevents/news/newsrecords/2011/04Apr/JamesClerkMaxwell.aspx
| publisher    = King's College London
| date         = 3 January 2017
| access-date  = 3 January 2017
| archive-url  = https://web.archive.org/web/20170104000418/https://www.kcl.ac.uk/newsevents/news/newsrecords/2011/04Apr/JamesClerkMaxwell.aspx
| archive-date = 4 January 2017
| url-status   = live
}}</ref><ref name="Maxwell">{{cite news
| title        = From Charles Mackintosh's waterproof to Dolly the sheep: 43 innovations Scotland has given the world
| url          = https://www.independent.co.uk/news/uk/home-news/charles-mackintosh-chemist-waterproof-google-doodle-scotland-inventions-innovation-bicycles-a7499911.html
| work    = The independent
| date         = 2 January 2016
| access-date  = 2 December 2017
| archive-url  = https://web.archive.org/web/20171002171029/https://www.independent.co.uk/news/uk/home-news/charles-mackintosh-chemist-waterproof-google-doodle-scotland-inventions-innovation-bicycles-a7499911.html
| archive-date = 2 October 2017
| url-status   = live
}}</ref> The foundation of virtually all practical color processes, Maxwell's idea was to take three separate black-and-white photographs through red, green and blue [[filter (photography)|filters]].<ref name="King's College" /><ref name="Maxwell" /> This provides the photographer with the three basic channels required to recreate a color image. Transparent prints of the images could be projected through similar color filters and superimposed on the projection screen, an [[additive color|additive method]] of color reproduction. A color print on paper could be produced by superimposing [[carbon print]]s of the three images made in their [[complementary color]]s, a [[subtractive color|subtractive method]] of color reproduction pioneered by [[Louis Ducos du Hauron]] in the late 1860s.
[[File:Colonel William Willoughby Verner, Sanger Shepherd process, by Sarah Acland 1903.png|thumb|left|Color photography was possible long before [[Kodachrome]], as this 1903 portrait by [[Sarah Angelina Acland]] demonstrates, but in its earliest years, the need for special equipment, long exposures, and complicated printing processes made it extremely rare.]]
Russian photographer [[Sergei Mikhailovich Prokudin-Gorskii]] made extensive use of this color separation technique, employing a special camera which successively exposed the three color-filtered images on different parts of an oblong [[photographic plate|plate]]. Because his exposures were not simultaneous, unsteady subjects exhibited color "fringes" or, if rapidly moving through the scene, appeared as brightly colored ghosts in the resulting projected or printed images.

Implementation of color photography was hindered by the limited sensitivity of early photographic materials, which were mostly sensitive to blue, only slightly sensitive to green, and virtually insensitive to red. The discovery of dye sensitization by photochemist [[Hermann W. Vogel|Hermann Vogel]] in 1873 suddenly made it possible to add sensitivity to green, yellow and even red. Improved color sensitizers and ongoing improvements in the overall sensitivity of [[Photographic emulsion|emulsions]] steadily reduced the once-prohibitive long exposure times required for color, bringing it ever closer to commercial viability.

[[Autochrome]], the first commercially successful color process, was introduced by the [[Auguste and Louis Lumière|Lumière brothers]] in 1907. Autochrome [[photographic plate|plates]] incorporated a [[mosaic]] color filter layer made of dyed grains of [[potato starch]], which allowed the three color components to be recorded as adjacent microscopic image fragments. After an Autochrome plate was [[reversal film|reversal processed]] to produce a positive [[reversal film|transparency]], the starch grains served to illuminate each fragment with the correct color and the tiny colored points blended together in the eye, synthesizing the color of the subject by the [[additive color|additive method]]. Autochrome plates were one of several varieties of additive color screen plates and films marketed between the 1890s and the 1950s.

[[Kodachrome]], the first modern "integral tripack" (or "monopack") color film, was introduced by [[Kodak]] in 1935. It captured the three color components in a multi-layer [[Photographic emulsion|emulsion]]. One layer was sensitized to record the red-dominated part of the [[visible spectrum|spectrum]], another layer recorded only the green part and a third recorded only the blue. Without special [[film processing]], the result would simply be three superimposed black-and-white images, but [[complementary color|complementary]] cyan, magenta, and yellow dye images were created in those layers by adding [[color coupler]]s during a complex processing procedure.

[[Agfa-Gevaert|Agfa's]] similarly structured [[Agfacolor]] Neu was introduced in 1936. Unlike Kodachrome, the color couplers in Agfacolor Neu were incorporated into the emulsion layers during manufacture, which greatly simplified the processing. Currently, available color films still employ a multi-layer emulsion and the same principles, most closely resembling Agfa's product.

[[Instant film|Instant color film]], used in a special camera which yielded a unique finished color print only a minute or two after the exposure, was introduced by [[Polaroid Corporation|Polaroid]] in 1963.

[[Color photography]] may form images as positive transparencies, which can be used in a [[slide projector]], or as color negatives intended for use in creating positive color enlargements on specially coated paper. The latter is now the most common form of film (non-digital) color photography owing to the introduction of automated photo printing equipment. After a transition period centered around 1995–2005, color film was relegated to a niche market by inexpensive multi-megapixel digital cameras. Film continues to be the preference of some photographers because of its distinctive "look".