Three-dimensional recording by laser scanning of the petroglyphs at Rombald's Moor, West Yorkshire

Abstract

A variety of methods have been used to depict and document petroglyphs, from hand sketching to close-range photogrammetry. Most methods, however, record only a two-dimensional image, whereas petroglyphs are by their nature three-dimensional. Additionally, most methods suffer from inaccuracies resulting from the skill and subjectivity of the recorder or distortions imposed by the equipment and conditions under which the panel was viewed. Conventional three-dimensional recording techniques such as the use of traditional moulding and casting materials, may damage the petroglyph itself. An assessment of the various shortcomings of established rock art recording methods resulted in the field-testing of laser scanning with the objective of obtaining a quantitative, three-dimensional record of petroglyph panels and the creation of non-contact replicas. This paper presents the principles behind laser scanning and an account of field trial results of laser scanning rock art in situ at Rombald's Moor, West Yorkshire, England. The work presented was undertaken as part of the Rock Art Pilot Project commissioned by English Heritage in July 1999.