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daguerreotypes ambrotypes composite daguerreotypes
Portrait of an unidentified man with a cane, ca. 1850s.
Portrait of an unidentified man with a cane, ca. 1850s. Quarter plate ambrotype. Photographer unknown.

The Ambrotype

Like a daguerreotype, an ambrotype is a unique positive-negative image, but the image is a collodion base developed on a glass plate and appears as a negative until dark lacquer is painted onto the back of the plate. Ambrotypes have a low-contrast, grey or white appearance to them, and are easily confused with tintypes. The ambrotype process was announced in 1851 by the American sculptor Frederick Scott Archer. As an inexpensive alternative to the daguerreotype, it soon surpassed the daguerreotype in popularity. It reached its peak circa 1860, but fell out of favor soon after with the introduction of the carte de visite albumen photograph.

Despite the popularity of the ambrotype, there are only a few of these images in the Princeton University Archives. As with daguerreotypes, ambrotypes were typically housed in miniature cases or protective frames. The gentleman with the cane pictured here may have been on the Princeton faculty, or he may have been an alumnus who sent in his ambrotype portrait to be hung in the college's Portrait Gallery.

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