Louis Jacques Mande Daguerre
French inventor, painter, and physicist. Born in Cormeilles-en-Parisis, France, November 18, 1789.
Daguerre perfected the daguerreotype, one of the first photographic methods of producing a lasting image. Daguerre also invented the diorama, a series of panoramic views illuminated by special lighting effects.
In 1826, Daguerre and the chemist Joseph Nicéphore Niépce began joint experiments with photographic processes. After Niepce died in 1833, Daguerre perfected the daguerreotype technique himself, making it public in 1839. He won considerable acclaim for his invention and was awarded a pension by the French government. He died in Petit-Brie-sur-Marne, France, July 12, 1851.
Daguerreotype was the first practical form of photograph.
Early daguerreotypes were made on polished silver-coated copper plates that were sensitized to light by treating them with iodine vapor.
After a sensitized plate had been exposed for from several minutes to half an hour in a camera, the picture was developed by putting the plate in a box containing mercury vapor for about 20 minutes.
The amount of mercury that was deposited on each part of the plate was proportional to the amount of light that had fallen on each part. In this way a positive picture was formed.
The picture was fixed, or made permanent, by washing with sodium thiosulfate, or hypo, and the image was usually toned with gold chloride to improve its quality.
In later daguerreotypes the sensitivity of the daguerreotype plates was increased by treating them with bromine vapor or chlorine vapor in addition to iodine vapor. The development of more sensitive plates together with the invention of a large-aperture short-focus camera lens reduced the times required for exposures to between 10 and 90 seconds.
Louis Jacques Mande Daguerre, a French painter and physicist, invented the daguerreotype process in 1839.
The process produced excellent pictures when properly carried out. It was widely used for portraits until late in the 19th century, when it was superseded by the wet collodion process, which was introduced in 1851.