MOV File
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Art & Architecture Thesaurus

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A variant of the wet collodion process to produce a direct-positive camera original. The collodion is coated on glass, the image underexposed and then underdeveloped, the glass backed with black lacquer or black cloth, and the whole mounted in a case or frame. Occasionally, the image was made on ruby glass.


ambrotype process

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The Portland Art Museum’s Online Collections site is brought to you thanks to support provided by the State of Oregon through its second Culture, History, Arts, Movies, and Preservation funding program and generous awards from the Institute of Museum and Library Services, the National Endowment for the Humanities, and the National Endowment for the Arts.