Madame Louise Georgina Daguerre, c 1845

Madame Louise Georgina Daguerre, c 1845. Daguerreotype taken by her husband, French physicist and photography pioneer Louis Jacques Mande Daguerre (1787-1851) at Bry-sur-Marne, France. Daguerre collaborated on his original photography research with Joseph Niepce (1765-1833). The daguerreotype process was the first widespread photographic method and used a copper plate with a highly polished silver surface sensitised by iodine fumes, exposed in a camera, and developed by fuming over warmed mercury, producing a reversed and unique image. Despite the amazing detail the daguerreotype produced, the delicate surfaces meant that they had to be encased behind glass. This, combined with the long exposure times involved, meant that it was not a practical photographic method. ©SSPL/National Media Museum