Creator: Unknown Date: c. 1855 Format: Photograph; collodion positive process / ambrotype Material: Paper Collection: The Royal Photographic Society Collection at the National Media Museum Inventory no: 2003-5001/2/20900 Blog post: Snappy 5th birthday Flickr Commons An English sculptor and photographer, Frederick Scott Archer (1813 - 1857) invented the wet collodion process for producing glass negatives in 1851 - undoubtedly one of the most important contributions to the progress of photography during the 19th century. He published his process freely and derived no personal benefit from it. He died penniless in 1857. Archer sits in a studio pose common at the time, pausing as if reading from a book, with heavily patterned drapes hanging at his left shoulder. The collodion positive process (also commonly known as ambrotype) was popular during the 1850s and 1860s. An underexposed collodion negative on glass was backed with a black opaque coating to create a unique positive image.