Presented here is a very condensed summary of the history of photography. For further study see the bibliography, timeline and podcast pages.

The first permanent photograph was an produced in 1826 by the French inventor Joseph Nicéphore Niépce. His photograph was produced on a polished pewter plate covered with a petroleum derivative called bitumen of Judea. Bitumen hardens with exposure to light. The unhardened material may then be dissolved in white petroleum. The metal plate was then polished, rendering a positive image with light regions of hardened bitumen and dark regions of bare pewter. Based on a Johann Heinrich Schultz discovery in 1727 that silver nitrate (AgNO3) darkens when exposed to light, Niépce then began experimenting with silver compounds.

Niépce soon started working in a partnership with Jacque Louis Mande Daguerre  and refined his existing silver process. In 1833 Niépce died of a stroke, leaving his notes to Daguerre. Daguerre discovered that exposing the silver first to iodine vapor before exposure to light, and then to mercury fumes after the photograph was taken a latent image developed and became visible. Bathing the plate in a salt bath then fixed the image in a permanent state. Consequently, on January 7, 1839 Daguerre announced that he had invented a process using silver on a copper plate called the daguerreotype, and displayed the first plate. The French government bought the patent and almost immediately made it public domain allowing photography to spread as a medium across the globe.

After reading about Daguerre's invention, William Henry Fox Talbot worked on perfecting his own process; in 1839 he acquired the knowledge of a crucial chemical, an effective fixer, from Sir John Herschel, who had previously discovered that hyposulfite of soda (also known as hypo, or now sodium thiosulfate) would dissolve silver salts. Later that year, Herschel made the first glass negative.

Talbot had invented the calotype process. He coated paper sheets with silver chloride to create an intermediate negative image. Unlike a daguerreotype, a calotype negative could be used to reproduce positive prints, like most chemical films do today. The calotype had yet another distinction compared to other photographic processes of the day, in that the finished product lacked fine clarity due to its translucent paper negative. This was seen as a positive attribute for portraits because it softened the appearance of the human face. Talbot patented his process, which greatly limited its adoption. He spent the rest of his life in lawsuits defending the patent until he gave up on photography. Later George Eastman refined Talbot's process, which is the basic technology used by chemical film cameras today. Hippolyte Bayard had also developed a method of photography but delayed announcing it, and so was not recognized as its inventor.

In 1839, John Herschel made the first glass negative (a term Herschel was the first to use in this context), but his process was difficult to reproduce. Nicephore Niépce's cousin, the chemist Niépce St. Victor published his invention of a process for making glass plates with an albumen emulsion; the Langenheim brothers of Philadelphia and John Whipple of Boston also invented workable negative-on-glass processes in the mid 1840s.

In 1851 Frederick Scott Archer invented the collodion process. which became widely used at the time. Photographer and children's author Lewis Carroll used this process, as does contemporary photographer Sally Mann.

Popularization of photography

The daguerreotype proved popular in responding to the demand for portraiture emerging from the middle classes during the Industrial Revolution. This demand, that could not be met in volume and in cost by oil painting, added to the push for the development of photography.

In 1847, Count Sergei Lvovich Levitsky designed a bellows camera which significantly improved the process of focusing. This adaptation influenced the design of cameras for decades and is still found in use today in some professional cameras. While in Paris, Levitsky would become the first to introduce interchangeable decorative backgrounds in his photos, as well as the retouching of negatives to reduce or eliminate technical deficiencies.

Roger Fenton and Philip Henry Delamotte helped popularize the new way of recording events, the first by his Crimean war pictures, the second by his record of the disassembly and reconstruction of The Crystal Palace in London. Other mid-nineteenth-century photographers established the medium by making a record of landscapes and architecture from around the world allowing people to see things they could never have seen without traveling to the sites themselves.

Because daguerreotypes were fragile and  one-of-a-kind and high public demand photographers encouraged chemists to refine the process of making many copies cheaply, which eventually led them back to Talbot's process.

Ultimately, the modern photographic process came about from a series of refinements and improvements in the first 20 years. In 1884 George Eastman, of Rochester, New York, developed dry gel on paper, or film, to replace the photographic plate so that a photographer no longer needed to carry boxes of plates and toxic chemicals around. In July 1888 Eastman's Kodak camera went on the market with the slogan "You press the button, we do the rest". Now anyone could take a photograph and leave the complex parts of the process to others, and photography became available for the mass-market in 1901 with the introduction of the Kodak Brownie camera. For the modern photographer processing black and white film, little has changed since the introduction of the 35mm film Leica camera in 1925.

The first digitally scanned photograph was produced in 1957. The digital scanning process was invented by Russell A. Kirsch, a computer pioneer at the National Institute of Standards and Technology. He developed the system capable of feeding a camera's images into a computer. His first fed image was that of his son, Walden Kirsch. The photo was set at 176x176 pixels.

Color Processes

Although color photography was explored throughout the 19th century, initial experiments in color resulted in projected temporary images, rather than permanent color images.

The first color photograph, was an additive projected image of a tartan ribbon, taken in 1861 by the Scottish physicist James Clerk Maxwell. Several methods for producing images were devised from 1862 on by two French inventors (working independently), Louis Ducos du Hauron and Charles Cros.

In 1851, Levi L. Hill announced a direct color process, he termed the Hillotype a process he claimed could produce permanent color images. His announcement created a lot of buzz and briefly halted the daguerreotype industry as the public wanted to wait for the new color process. Despite having his personal examples, Hill didn't produce a formula to back up his claims, he was denounced as a fraud.

The first fully practical color plate, called an Autochrome, did not reach the market until 1907. It was based on a screen-plate method, the screen (of color 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 the screen restores colors approximating the original.

Over the subsequent years several short lived color processes were announced and patented. These processes included the Finlay process, Dufaycolor and the Carbro process.

Between 1911 and 1914 Rudolph Fischer and Karl Schinzel invented a color film that utilized color couplers in the emulsion. This technology became the basis for color films to this day.  In 1930 Kodak Research Laboratories hired Leopold Godowsky, Jr. and Leopold Mannes who after working on the process announced the first truly successful subtractive reversal film in 1935. The film they created was dubbed Kodachrome. Kodachrome became widely successful and was in use until 2009 when the Kodak company announced it would "retire" the film.

In 1936 Agfa released their own color transparency film, and in 1939, their own color negative film. Kodak followed up their product lines with a color negative film Kodacolor in 1942. For Kodacolor film Kodak developed the c-41 chemical process for development of the color negative film. It is still the standard in use today.