Madame Louise Georgina Daguerre, c 1845.
© National Media Museum / Science & Society Picture Library
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 proces 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 glas. This, combined with the long exposure times involved, meant that it was not a practical photographic method.