Colorized Ambrotype "child Portrait" Maison Duval

Ambrotype portrait of a young child seated delicately colored In a blackened wooden frame Napoleon III (Frame format: 19 x 17 cm) On the back label from Maison DUVAL in Angers. Patented in 1854 by James Ambrose Cutting, an ambrotype is a negative on a glass plate, when viewed transparently, which becomes a positive when placed in front of a black background. The ambrotype was commonly used from 1854 until the 1870s. Less expensive and requiring a much faster exposure time than the daguerreotype, it was widely used by portrait painters. To obtain the negative of this unique object, a previously cleaned glass plate is covered with a layer of collodion. After drying, a transparent varnish is applied, as well as sometimes color highlights. Presented on a black fabric or paper background, it is delivered set in a union case or in a frame as for daguerreotypes, which often creates confusion in the identification of these two processes.
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