History of the camera-02
Early fixed images
The first partially successful photograph of a camera image was made in approximately 1816 by Nicéphore Niépce, using a very small camera of his own making and a piece of paper coated with silver chloride, which darkened where it was exposed to light. No means of removing the remaining unaffected silver chloride was known to Niépce, so the photograph was not permanent, eventually becoming entirely darkened by the overall exposure to light necessary for viewing it. In the mid-1820s, Niépce used a sliding wooden box camera made by Parisian opticians Charles and Vincent Chevalier to experiment with photography on surfaces thinly coated with Bitumen of Judea. The bitumen slowly hardened in the brightest areas of the image. The unhardened bitumen was then dissolved away. One of those photographs has survived.
Daguerreotypes and calotypes
After Niépce's death in 1833, his partner Louis Daguerre continued to experiment and by 1837 had created the first practical photographic process, which he named the daguerreotype and publicly unveiled in 1839. Daguerre treated a silver-plated sheet of copper with iodine vapor to give it a coating of light-sensitive silver iodide. After exposure in the camera, the image was developed by mercury vapor and fixed with a strong solution of ordinary salt (sodium chloride). Henry Fox Talbot perfected a different process, the calotype, in 1840. Both used cameras that were little different from Zahn's model, with a sensitized plate or sheet of paper placed in front of the viewing screen to record the image. Focusing was generally via sliding boxes.
Collodion dry plates had been available since 1855, thanks to the work of Désiré van Monckhoven, but it was not until the invention of the gelatin dry plate in 1871 by Richard Leach Maddox that they rivaled wet plates in speed and quality. Also, for the first time, cameras could be made small enough to be hand-held, or even concealed. There was a proliferation of various designs, from single- and twin-lens reflexes to large and bulky field cameras, handheld cameras, and even "detective cameras" disguised as pocket watches, hats, or other objects.
The shortened exposure times that made candid photography possible also necessitated another innovation, the mechanical shutter. The very first shutters were separate accessories, though built-in shutters were common by around the start of the 20th century.
Abu Kalam Shamsuddin
Department of MCT