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The word comes from the Greek words φως phos ("light"), and γραφις graphis ("stylus", "paintbrush") or γραφη graphê, together meaning "drawing with light" or "representation by means of lines", "drawing".
Most commonly a camera or camera obscura is the image forming device and photographic film or a digital storage card is the recording medium, but other methods are available. For instance, the photocopy or xerography machine forms permanent images but uses the transfer of static electrical charges rather than photographic film, hence the term electrophotography. The rayographs published by Man Ray in 1922 are images produced by the shadows of objects cast on the photographic paper, without the use of a camera. And one can place objects directly on the glass of a scanner to produce pictures electronically.
Photographers control the camera to expose the light recording material (usually film) to light. After processing, this produces an image whose contents are acceptably sharp, bright and composed to achieve the objective of taking the photograph.
The controls include:
The controls are usually inter-related, for example brightness is aperture multiplied by shutter speed, and varying the focal length of the lens will allow greater control over the depth of field.
Photography can be classified under imaging technology and has gained the interest of scientists and artists from its inception. Scientists have used its capacity to make accurate recordings, such as Eadweard Muybridge in his study of human and animal locomotion (1887). Artists have been equally interested by this aspect but have also tried to explore other avenues than the photo-mechanical representation of reality, such as the pictorialist movement. Military, police and security forces use photography for surveillance, recognition and data storage.
The camera is not a modern invention, the camera obscura and the camera lucidaSee Camera Lucida for the book by French literary critic Roland Barthes. A camera lucida is an optical device used as a drawing aid by artists. It was invented in 1807 by Dr. The camera lucida performs an optical superimposition of the subject being viewe were used by artists to trace scenes as early as the 16th century15th century 16th century 17th century more centuries) As a means of recording the passage of time, the 16th century was that century which lasted from 1501 to 1600. Events Beginning of the " Little Ice Age" a cooling period that resulted in lower crop yi. These early cameras did not fix an image in time, they only projected what was before the lens onto a surface.The first photographA photograph (often just called a photo is an image (or a representation of that on e. paper) created by collecting and focusing electromagnetic radiation. The most common photographs are those created of visible wavelengths, producing permanent records o is considered to be an image produced in 1825Events January 4 King Ferdinand I of the Two Sicilies dies and is succeeded by his son Francis I of the Two Sicilies. February 9 After no presidential candidate received a majority of electoral votes, the United States House of Representatives elects John by Nicéphore Niépce on a polished pewterPewter is an alloy, traditionally of anywhere between three and nine parts tin, and one part lead. Modern pewter mixes the tin with copper, antimony and/or bismuth, as opposed to lead. The metal is gray in colour and generally has a dull finish. A pewter plate covered with a petroleumNodding donkey pumping an oil well near Sarnia, Ontario, 2001 Petroleum (from Latin petrus rock and oleum oil), mineral oil or crude oil sometimes colloquially called black gold is a thick, dark brown or greenish flammable liquid, which exists in the uppe derivative called bitumenBitumen is a category of organic liquids which are highly viscous, black, sticky and wholly soluble in carbon disulfide. Asphalt and tar are the most common forms of bitumen. In British English, 'bitumen' is often used interchangeably with both 'asphalt' of Judea. It was produced with a camera, and required an eight hour exposure in bright sunshine. However this process turned out to be a dead end and Niépce began experimenting with silver compounds based on a Johann Heinrich Schultz discovery in 1724 that a silver and chalk mixture darkens when exposed to light. That is, Schultz discovered that tarnished, or rusted, silver refects less light than untarnished silver.
Niépce and the artist Jacques Daguerre refined the an existing silver process in a joint partnership. In 1833 Niépce died unexpectedly of a stroke, leaving his notes to Daguerre. While he had no scientific background, Daguerre made two pivotal contributions to the process. He discovered that by exposing the silver to mercury fumes after the photograph was taken a latent image could be exposed in just minutes, by then bathing the plate in a salt bath the image could be [fixed_photograph|fixed]. In 1839 Daguerre announced that he had discovered a means to fix developed a process using silver on a copper plate called the Daguerreotype; a very similar process is still used today for Polaroids®.
Across the English Channel, William Fox Talbot had earlier discovered another means to fix a silver process image but had kept it secret. After reading about Daguerre's invention, Talbot refined his process, so that it might be fast enough to take photographs of people as Daguerre had done, and by 1840 he had invented the calotype process. He coated paper sheets with silver chloride to create an intermediate negative image. Unlike a daguerrotype, a calotype negative could be used to reproduce positive prints, like most chemical cameras do today. Talbot patented this process, which greatly limited its adoption. He spent the rest of his life in lawsuits defending the patent until he gave up on photography all together. But later this process was refined by George Eastman and is today the basic technology used by chemical film cameras. Hippolyte Bayard also developed a method of photography, but delayed announcing it and so was not recognized as its inventor.