The ambrotype process is named after James Ambrose Cutting (1814-1867) who popularised the process and patented in 1854 a method of mounting and sealing the image plate. Cutting was not the inventor and actually it’s not a new process, but a variant of the wet plate collodion process. An ambrotype is an underexposed collodion negative. A positive image appears when the glass plate is placed on a dark background. This was noticed the first time by Louis-Désiré Blanquart-Evrard in 1850[1]. Ambrotypes were much more affordable than daguerreotypes and became known as the poor man’s daguerreotype[2]. The process was popular between 1852 and 1870[1].
The 8,5x17cm stereo ambrotype in this post shows an image of two men and a boy. The collodion negative is covered by a cover glass to protect the emulsion. There is a cardboard bottom under the collodion plate which ensures that the negative can be viewed as a positive image. The three layers are held together by binding tape. The image is decorated by a gold fillet. These kind of decorations can also be seen in the glass stereoviews of Ferrier & Soulier.
The stereo ambrotype is a glass stereoview but the image should be viewed with reflective light when using a stereoscope because the glass plates are not translucent due to the cardboard bottom.
References
- Lavédrine, Betrand. Photographs of the Past – Process and Preservation, 2009, p.50
- Ambrotype – via: graphicsatlas.org