Three-dimensional documentation and virtual restoration of the Lichfield Angel

Abstract

The Lichfield Angel is a remarkable survival of early medieval sculpture, discovered during the recent excavation of the Cathedral's nave. Dating from around 800AD, the limestone panel is carved with the figure of an archangel, which retains an unprecedented amount of original painted decoration. Given the panel's exceptional importance, a carefully sequenced programme of recording and analysis was commissioned to inform decisions about the Angel's conservation and display. Close-range three-dimensional laser scanning comprised an essential component of the project's integrated documentation strategy. This paper outlines the scanning process and the image mapping technique used to create high resolution three-dimensional models of the Angel's three fragments. It explores the novel applications for which the scan data was used, including high-resolution three-dimensional digital 'basemaps' onto which conservators could record and interrogate information about the fragments' condition and technique. A final section describes the surface colour reconstruction techniques used to 'virtually' restore the Angel's painted decoration. © 2009 Icon, The Institute of Conservation.