Date/Time: 1 Jul 2019 - 2 Jul 2019
Tutor(s): Hildegard Homburger
In this course, to be held at The National Archives, London, the major photoreproduction processes, (Cyanotype, Vandyke print, Ferrogallic print, Diazotype, Silver gelatine contact print, Gel lithography, Negrography), will be explained historically and technically.
Until the introduction of computers, photoreproduction was the common means to make same size contact copies of architectural drawings without using photographic equipment. Photoreproductions, are found today in architectural collections, archives, and also in art collections. They were made by taking a technical drawing which had been drawn on translucent material and placing it against an equal sized photosensitised sheet and exposing it to light. The light sensitive carrier was most often paper. The components of the chemical solutions within the sensitized layers of these photoreproductions vary depending on the photoreproduction process. The resulting sensitivity of photoreproductions towards light and environmental conditions require special attention and care when considering storage and exhibition.
Participants will examine under magnification a great number and variety of original copies and identify the photoreproduction processes. The conservation (storage, exhibition and treatment) of these different photoreproductions is discussed.