Editing Collodion (section)

==Dry collodion plates==

Richard Hill Norris, a doctor of medicine and professor of physiology at [[Queen's College, Birmingham]] (a predecessor college of [[Birmingham University]]),<ref>{{cite web | url=http://archiveshub.ac.uk/data/gb150-us41 | title=University of Birmingham Staff Papers: Papers of Dr Richard Hill Norris - Archives Hub}}</ref> is generally credited with the first development of dry collodion plate when in 1856 he took out a new patent for a [[dry plate]] used in [[photography]] in which the emulsion was coated with [[gelatine]] or [[gum arabic]] to preserve its sensitivity. Another method, using tannin, invented by Major C. Russell in 1861, followed and in 1864 W.E. Bolton and E.J. Sayce mixed [[silver bromide]] with collodion, so that by the mid-1860s the wet-plate process was being replaced.<ref>Hannavy, John (ed.) (2008) Encyclopedia of nineteenth-century photography: A–I, Volume 1, Taylor & Francis, p. 440</ref>