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Hyppolyte Bayard, who had exhibited a system of capturing permanent images a month before the unveiling of the daguerreotype, Daguerre’s method had several drawbacks as a practical system of photography. The system used copper plates coated with a silver halide that underwent chemical change when exposed to light. Mercury vapor would then be passed over the plates, creating an amalgam with the silver, and after washing, a fixed image of great clarity was revealed. However, the copper plates were expensive and dangerous to develop as mercury vapor is highly toxic. The exposure times were extremely long – up to three minutes depending on the light – and this limited the types of objects that could be photographed. The major drawback, though, was that the daguerreotype produced a single positive image from which copies could not be easily made. Nonetheless, the daguerreotype enjoyed considerable success on the Continent and elsewhere, particularly in those situations where only single images of stationary objects were required. An early use was the photographing of the monuments and buildings of France, commissioned by the French government; and in the US in the 1860s Brady still used the daguerreotype, in part for its clarity and in part because of licensing problems with the other major photographic system, the calotype. _Î_ The aesthetic context of early photography: The second major discourse that took charge of the P90
S E R I A L PAG E I D E N T I F I C AT I O N N o. :
THE TRAJECTORY OF THE IMAGE ...