Film photography is possible thanks to the small advancements made over decades. Thomas Wedgewood started experimenting with light-sensitive chemicals in 1792 and made the first unfixed photographic picture. However, in 1826 Joseph Nicephore Niepce coated a tin plate with asphalt, put it in a camera obscura and left it pointed out of a window for eight hours until the areas of that had not been hardened by the sun washed off in oil.  Louis Jacques-Mande Daguerre used silver iodide-coated silver plates exposed to light in a camera and then treating the plate with Mercury vapor and a strong salt solution to remove the leftover iodide. Daguerre and Niepce knew they were working on similar concepts and decided to collaborate. By 1837, Daguerre used sodium thiosulfate to create his “heliographs” which became known as “Daguerreotypes.”

Photography processing is a process that involves several chemicals and use of or lack of light. Through putting the film in these chemical bathes for a certain amount of time and then using a solution to stop the development in a dark room. Then the negative image and light is used to print an image. Photographs are developed in a dark room due to the light-sensitive materials that go into the process. To understand the process, one must understand that the chemicals included in the process are silver halide crystals, the chemical compound that forms between silver and halogens (reactive nonmetallic elements) and reducing agents that can break down silver. The film from a camera is treated by reducing agent chemicals which the silver in the silver halide crystals is reduced which creates a negative of the image where the light parts look dark and the dark parts look light.