J.CAC VOLUME 36 (2011)
Recording the Weathering of Outdoor Stone Monuments Using Reflectance Transformation Imaging (RTI): The Case of the Guild for All Arts (Scarborough, Ontario)
Reflectance Transformation Imaging (RTI), developed in 2001 at Hewlett-Packard (HP) Labs, has been available for almost a decade but has been largely overshadowed by the rapid growth of laser and structured-light scanning in many cultural heritage applications. Work by Cultural Heritage Imaging (CHI) in San Francisco and at the University of Minho, Portugal, has done much to promote the technology and to develop a standard workflow. Demonstrated in this technical note is the way RTI can be integrated into the toolkit of the working stone conservator. The case of weathered façades in sandstone and limestone at Guild of All Arts in Scarborough, Ontario will be considered and the potential of RTI to reveal original tool marks on stone as well as spalling, both features that can be difficult to capture reliably outdoors with standard photography. RTI promises, by virtue of its ease-of-use and low-cost, to become a standard tool of documentation among conservation and heritage professionals for before and after-treatment recording.
Download: JCAC36 Gabov & Bevan