Preferred label
Ambrotypes
Alternative labels
Cased photographs
Collodion positive photographs
Broader term
Photographs
Scope note
Direct-image photographs; the chemically reduced collodion glass negative packaged against a dark background appears as a positive. Commonly in a case; popular mid-1850s to mid-1860s.
Editorial note
Used in a note under PHOTOGRAPHS.
Change note
Formerly TGMI term & TGMII term.