The word photography comes from the greek words phōs (genitive: phōtós) light and gráphein, to write. The first permanent photograph was produce in 1826 by Joseph Nicéphore Niépce (a French inventor). To produce his photographs he used a polished pewter plate covered with a petroleum derivative called bitumen of Judea which he then dissolved in white petroleum. Bitumen hardens with exposure to light and then the unhardened material can be washed away and the metal plate polished which leaves a positive image with light areas of hardened bitumen and dark areas of bare pewter. Niépce then went on to experiment with silver compounds based on Johann Heinrich Schultz’s discovery in 1727 that silver nitrate darkens when exposed to light. Niépce died in 1833 and left his notes to Louis Daguerre who made two contributions to the process – firstly, that exposing the silver to iodine vapour before exposing it to light then to mercury fumes after the photograph was taken it would form a latent image and secondly, that bathing the plate in a salt bath fixed the image. Six years after Niépce’s death Daguerre announced that he had invented a process using silver on a copper plate, the French government bought the patent and made it a public domain. For many years after this a variety of artists and inventors continued to use their own processes or improved on previous ones until in 1847, Count Sergei Lvovich Levitsky designed a bellows camera which improved the process of focusing significantly. This influenced the designs of cameras for decades and is still used in some professional cameras today.
The modern photographic process came from George Eastman in 1884 by developing dry gel on paper (or film) to replace the photographic plate so the photographer no longer needed to carry boxes of plates and toxic chemicals around. In summer 1888 Eastman’s Kodak camera went on the market so anyone could take a photograph and leave the complicated part of the process to others. In the 20th century photography continued to develop as a commercial service. Little had changed since the introduction of the 35mm Leica film camera in 1925 for the modern photographer processing black and white film. In 1957, the first digitally scanned photograph was produced; this digital scanning process was invented by Russell A. Kirsch. He developed a system capable of feeding a camera’s images into a computer and his first fed image was of his son which was set at 176x176 pixels.
Colour photography was first explored throughout the 19th century however initial experiments only resulted in projected temporary images rather than permanent ones; until the 1870’s the emulsions available were not sensitive to red or green light. The three-colour method was first suggested in an 1855 paper on colour vision by James Clark Maxwell. It is based on the fact that the normal human eye sees colour because its inner surface is covered with millions of cone cells of three types – one more sensitive than the others to the end of the spectrum we call ‘red’, one more sensitive to the middle or ‘green’ area and one which is strongly stimulated by ‘blue’. The first colour photograph was taken in 1861 by Thomas Sutton and used Maxwell’s idea of a set of three monochrome ‘colour separations’. It was of a tartan ribbon that was made up of a variety of colours including red and green. A variety of methods for producing images were devised from 1862 on-wards by two French inventors – Louis Ducos du Hauron and Charles Cros. Then in 1873 and 1884, Hermann W. Vogel found a method to sensitize silver halide film to green and orange light however full sensitivity to red light was not achieved until the early 20th century. The first fully practical plate, Autochrome, didn’t reach the market until 1907. It was based on a screen-plate method; the screen of filters being made using dyed dots of potato starch. The screen lets filtered red, green or blue light through each grain to a photographic emulsion in contact with it. The plate is then developed to a negative and reversed to a positive which when viewed through a screen resoles colours approximating the original. Another system of colour photography, created by Sergei Mikhailovich Prokudin-Gorskii, involved three separate monochrome exposures of a still scene through red, green and blue filters which required a special machine to display but had impressive results even by modern standards. His collection of glass plates was purchased from his heirs by the Library of Congress in 1948 and is now available in digital images.
The first true digital camera that recorded images as a computerised file was the Fuji DS-1P which recorded to a 16MB internal memory card; it was never marketed in the United States. The first digital camera placed on the market was the 1990 Dycam Modal 1 (also sold as the Logitech Fotoman). It used a CCD image sensor, stored pictures digitally and connected directly to a computer for download. CCD stands for charge-coupled device which is a device for the movement of electrical charge usually from within the device to an area where the charge can be manipulated - it was invented in 1969 by Willard Boyle and George E. Smith.
In 1999 the Nikon D1 was introduced which was a 2.74 mega-pixel camera, the first DSLR (digital SLR). DSLR stands for digital single-lens reflex and the majority on DSLRs are digital cameras that use a mechanical mirror system and pentaprism to direct light from the lens to an optical view finder on the back of the camera. These cameras are preferred by professional photographers as they allow an accurate preview of framing close to the moment of exposure and allow the photographer to choose from a variety of interchangeable lenses.
Photography has come a long way from its discovery in 1826. In just under 200 years our population has gone from using plates to produce images to the highest standards of DSLRs however a variety of film cameras (including 35mm, medium-format, pinhole, and more) are still used by a number of professional photographers. There is a huge quantity of cameras – both old and modern – to choose from now-a-days if you’re considering a career in photography or just as a hobby.
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