Gravestone in Bry-sur-Marne of Louis Jacques Mande Daguerre (1787-1851). Daguerre collaborated on his original photography research with Joseph Niepce (1765-1833). The daguerreotype proces, the first widespread and practical photographic proces, was announced to the French Academy of Sciences on 9 January 1839. The proces comprises a copper plate with a highly polished silver surface sensitized by iodine fumes, exposed in a camera, and developed by fuming over warmed mercury, producing a reversed and unique image.
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