Daguerre process

Studies of surfaces and surface properties can be traced to the early 1800s [1]. Processes that involved surfaces and surface chemistry, such as heterogeneous catalysis and Daguerre photography, were first discovered at that time. Since then, there has been a continual interest in catalysis, corrosion and other chemical reactions that involve surfaces. The modem era of surface science began in the late 1950s, when instmmentation that could be used to investigate surface processes on the molecular level started to become available. 

L. J. M. Daguerre s photographic process (silver plate sensitized by exposure to iodine vapour)... 

The first permanent images were obtained by the French landowner . N. Niepce using bitumcn-coated pewter (bitumen hardens when expo.sed to light for several hours and the unexposed portions can then be dissolved away in oil of turpentine). He then helped the portrait painter, L. J. M. Daguerre, to perfect the daguerreotype process which utilized plates of copper coated with silver sensitized with iodine vapour. The announcement of this process in 1839 was greeted with enormous enthusiasm but it. suffered from the critical drawback that each picture was unique and could not be duplicated. 

The possibility of developing the latent image was discovered by Daguerre, who at first employed a silver plate coated with the iodide, development being effected by exposing the plate to the action of mercury-vapour. Later, he substituted glass for silver, and developed with a mixture of silver nitrate and ferrous sulphate. His discovery led to the introduction of the wet collodion-process with silver iodide as the sensitive material. 

L. J. M. Daguerre s photographic process (silver plate sensitized by exposure to iodine vapour) Introduction of (light sensitive) AgBr into photography Iodine (as iodate) found in Chilean saltpetre by A. A. Hayes... 

Through further optical and chemical processes that need not be described here, a realistic portrayal of the scene is eventually obtained. The process is termed photography ( light-writing ). A number of men contributed to the new technique, including the French physicist Joseph Nicephore Niepce (1765-1833), the French artist Louis Jacques Mande Daguerre (1789-1851), and the English inventor William Henry Fox Talbot (1800-77). 

Daguerreotype (Jacques Daguerre) Improving on the discoveries of Joseph Nicephore Niepce, Daguerre develops the first practical photographic process, the Daguerreotype. 

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