Original daguerreotype from J. L. M. Daguerre. Very rare. Gold-toned in a toning bath in a process presented to the public in 1840. The picture was restored in 1913 by E. Stenger and in 1955 by R. Skopec. It is one of the two Daguerre works in Czech Republic

A collection of portraits from National Technical Museum, Prague, Czech Republic. National Technical Museum in Prague, established in 1908, assembled documents of the development of many technical fields, natural and exact sciences, and of industry on the territory of today’s Czech Republic.

Invented by Louis Daguerre and introduced worldwide in 1839,[3][4][5] the daguerreotype was almost completely superseded by 1856 with new, less expensive processes, such as ambrotype (collodion process), that yield more readily viewable images. There has been a revival of the daguerreotype since the late 20th century by a small number of photographers interested in making artistic use of early photographic processes. The first authenticated image of Abraham Lincoln, a daguerreotype of him as U.S. Congressman-elect in 1846, attributed to Nicholas H. Shepard To make the image, a daguerreotypist polished a sheet of silver-plated copper to a mirror finish; treated it with fumes that made its surface light-sensitive; exposed it in a camera for as long as was judged to be necessary, which could be as little as a few seconds for brightly sunlit subjects or much longer with less intense lighting; made the resulting latent image on it visible by fuming it with mercury vapor; removed its sensitivity to light by liquid chemical treatment; rinsed and dried it; and then sealed the easily marred result behind glass in a protective enclosure.