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Very nice and rare daguerreotype * the portrait of a man, in a case frame, antique 1850 nineteenth century.
This daguerreotype is in good condition ..
A note: some wear time on the context, micro-scratches, the daguerreotype is a little past the edges (mostly right), see photos.
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* The daguerreotype term comes from the name of its inventor, artist and French decorator Daguerre, who discovers this process in 1835. After years of development, he presented his discovery to the French Academy of Sciences on January 9, 1839. The daguerreotype is a solely positive process allowing no reproduction of the image. It consists of a plate, generally made of copper, coated with a silver layer. This plate is sensitized to light by exposure to iodine vapor, and in combining with silver, produce photosensitive silver iodide. When exposed to light, the plate receives a hidden image, called "latent image". Development of the image is performed by placing the plate exposed above a slightly heated mercury vessel (75 ° C). Mercury vapor condenses on the plate and combines with the silver iodide forming amalgam only where the light acted proportion to the intensity thereof. The image thus produced is very fragile and can be removed by heating the plate, which produces the evaporation of the mercury from the amalgam.
