Self portrait with dogs; Sawai Ram Singh II; c. 1870; Digital print from an original wet collodion glass plate negative. Photograph: Nous (2023), Wikimedia Commons

A photographic negative produced using a glass plate coated with a light-sensitive emulsion of silver compounds, in use in plate cameras until the early twentieth century. A precursor of the film negative, it took the form of the collodion wet plate method between 1851 and the 1880s, and later, the gelatin dry plate method.