Cameras
The first of the cameras was the camera obscura. It was a dark chamber (in Latin, a camera obscura, demonstrating the etymology), "consist[ing] of a darkened chamber or box, into which light is granted through a pinhole (later a convex lens), forming an image of external objects on a surface of paper or glass, etc., placed at the focus of the lens". In the 6th century, Greek mathematician and architect Anthemius of Tralles implemented a type of camera obscura in his experiments. The camera obscura was explained by the Arabic scientist Ibn al-Haytham (Alhazen) in his Book of Optics (1015–1021). Scientist-monk Roger Bacon also researched the matter. The real name of camera obscura was applied by mathematician and astronomer Johannes Kepler in his Ad Vitellionem paralipomena of 1604. He later added a lens and made the device transportable, in the form of a tent. Irish scientist Robert Boyle and his assistant Robert Hooke created a portable camera obscura in the 1660s.
The first camera obscura that was small and portable enough for practical use was constructed by Johann Zahn in 1685. At this time there was no way to keep the images produced by these cameras apart from manually tracing them. However, in 1724, Johann Heinrich Schultz found that a silver and chalk mixture darkens under exposure to light. Early photography built on these discoveries and advancements. The early photographic cameras were typically similar to Zahn's camera obscura, though usually with the addition of sliding boxes for focusing. Before each exposure, a sensitized plate would be inserted in front of the viewing screen to capture the image. The first permanent photograph was performed in 1826 by Joseph Nicéphore Niépce using a sliding wooden box camera made by Charles and Vincent Chevalier in Paris and building on Johann Heinrich Schultz's discovery about silver and chalk mixtures darkening when exposed to light. Jacques Daguerre's popular daguerreotype process utilized copper plates, while the calotype process invented by William Fox Talbot captured images on paper.
The development of the collodion wet plate process by Frederick Scott Archer in 1850 cut exposure times dramatically, but needed photographers to prepare and develop their glass plates on the spot, usually in a mobile darkroom. Despite their complexity, the wet-plate ambrotype and tintype processes were in extensive use in the latter half of the 19th century. Wet plate cameras were little different from previous designs, though there were some models, such as the sophisticated Dubroni of 1864, where the sensitizing and developing of the plates could be made out inside the camera itself rather than in a separate darkroom. Other cameras were corresponded with multiple lenses for making cartes de visite (a type of small photograph). It was during the wet plate era that the use of bellows for focusing became extensive.
The earliest color photograph was made by Scottish physicist James Clerk Maxwell, with the help of English inventor and photographer Thomas Sutton, in 1861.
The electronic video camera tube was invented in the 1920s, starting a line of development that eventually resulted in digital cameras, which largely replaced film cameras after the turn of the 21st century.