Photography
Photography is the recording of visible images by focusing light on light-sensitive materials. English astronomer Sir John Herschel (1792-1871) first used the term photography in 1839. The word comes from the Greek photos, meaning light, and graphos, meaning writing.
There are many forms of photography. Still photography captures individual self-contained images on single sheets of film. Portraits are an example of still photography. Motion photography, also called cinematography, records a series of images illustrating a subject in motion. These photographic images are focused onto a screen using a movie projector. Television, video, even medical x rays are based on the principles of photography.
The predecessor to the modern handheld camera was the camera obscura. This giant, cumbersome device consisted of a dark box or room with a tiny hole in one wall. When peered through the tiny opening, an inverted image could be seen on the opposite wall. Leonardo da Vinci described this early form of photography in a manuscript dated 1519. Today such cameras are used by astronomers and physicists to document high energy reactions.
Two distinct optical and chemical scientific processes combined to make photography possible. Although scientists knew as early as the 1600s that the chemicals now used for photography darkened when exposed, they believed the reaction was caused by air or heat, not by light. Inventors did not discover the importance of light in photography until 200 years later.
The first person to create a photograph in the camera obscura was Joseph-Nicéphore Niepce (1765-1833), a French lithographer. In the summer of 1827, Niepce focused light on an asphalt solution for eight hours to create his picture.
In January 1829, Niepce partnered with the man who eventually was regarded as the inventor of modern photography, Louis-Jacques-Mandé Daguerre (1789-1851). Although Niepce died four years later, Daguerre continued to experiment. Daguerre used a camera consisting of two boxes sliding inside one another. At 50 lb (18kg), the device was cumbersome, but smaller models soon appeared.
After nearly a decade of trial and error, Daguerre discovered a way of developing photographic plates that significantly reduced Niepce's exposure time from eight hours to just 30 minutes. He also documented that an image could be made permanent or fixed by immersing it in a salt solution. He called his image the Daguerreotype. The Daguerreotype became the first commercially utilized photographic process. Yet, the daguerreotype eventually proved unpopular because of its unique positive images, and the fact that it was expensive and could not be mass-produced. By 1851, this novel new art form was abandoned.
The negative-positive photographic process in use today was the idea of William Henry Fox Talbot (1800-1877), a British amateur scientist. His calotype (later called the talbotype) used paper negatives to yield positive pictures. Inevitably, however, imperfections embedded in the paper were printed along with the image. Compared with Daguerreotypes, the quality of Talbot's images were rough. However, the fact that an unlimited number of positive prints could be created made it an attractive technique. To perfect Talbot's process, many tried to substitute glass for paper. However, the silver solution needed for exposure would not stick to the shiny glass surface.
A solution was offered in 1848, when a nephew of Niepce, Calude-Félix-Abel Niepce de Saint-Victor (1805-1870), coated the glass plate with an egg white solution. The new process, called albumen photography, allowed for very fine detail and much higher photographic quality. Its slow speed, however, made the technique impossible for portraiture use. Saint-Victor also brought the world the first color images. Saint-Victor and French physicist Alexandre-Edmond Becquerel produced the colors using treated silver chloride coatings. The team hit a roadblock when they failed to fix the final photograph. Scientists would try again several decades later.
In 1851, English sculptor Frederick Scott Archer (1813-1857) launched a new era in photography. His development of the wet plate allowed for much faster processing speeds. This process used a glass plated coated with a nitrocellulose (collodion) solution containing potassium iodide. The plate was placed in a silver nitrate solution, then exposed inside the camera while still wet. The substance was the first light-sensitive material to allow instantaneous exposure in adequate light.
Archer's wet-collodion plate quickly became the principal photographic process. The first news and feature photographers used the new technique to document the Civil and Crimean wars. But the material's tendency to rapidly evaporate if not immediately developed meant photographers traveled with cumbersome portable darkrooms. Graphic artists, on the other hand, embraced the high-quality, fine-grain negatives and kept the process in use until the middle of the twentieth century. At the same time of Archer's important development, Talbot demonstrated the first high-speed flash photograph using a spark from a battery.
In 1859, Britain's James Clerk Maxwell discovered that colors from an image could be reproduced by combining red, green, and blue light in various proportions. Nearly a decade later, Frenchmen L. Ducos du Hauron and C. Clos suggested a new way to form color pictures. The pair's idea to superimpose dye images (subtractive color synthesis) as a means of forming color images provided the basis of assembly color-print processes from the 1890s onward.
The next major step forward in photographic processing came in 1871, when gelatin was used instead of glass as a basis for the photographic plate. The invention meant photographers were no longer required to coat and sensitize their own processing materials. The new dry plate technique produced images much faster than with any previous technique. The simple fact that dry-plates could be made and stored for months revolutionized photographic development. Ready-made emulsions were on sale by 1873.
In 1888, George Eastman (1854-1932) introduced the first box camera, complete with a roll of negative paper, and processing and printing service. His slogan, "You push the button, we do the rest," helped popularize photography. Several other camera designs quickly followed. In 1924 the first commercially successfully miniature camera, the Leica, hit the market. The 24 x 36 mm camera was extremely portable and easy to use, and eventually became the photojournalist's standard.
In the twentieth century, photography emerged into a mass hobby. No longer was photography considered the peculiar cousin of painting; instead it was regarded as a unique and evolving art form. By the mid 1900s, consumers could see the photographs they snapped in just seconds using Edwin Herbert Land's instant film and Polaroid camera. In 1950, Eastman Kodak's Kodachrome film was widely marketed for all photographers. The Polaroid Land Company followed suit with the introduction of instant color film in 1963.
As technology advanced, so has the scope of photography. In the 1980s, Sony introduced the first personal camcorder, bringing motion photography into the hands of amateurs. Shortly after, scientists with Kodak created the world's first digital sensor capable of recording more than a million image elements. The feat resulted in the production of 5 x 7 in (12.7 x 17.8 cm) digital prints that looked like photographs. In the 1990s, digital photography escalated as Nikon, Canon, Leaf Systems, Kodak, and others announce new digital cameras for amateurs and professionals alike.
By the beginning of the twenty-first century, photography is considered more than an art form; it is an invaluable means of communication and history preservation. The average person in the United States typically encounters more than 1,000 camera images a day.
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