Reflectance Transformation Imaging (RTI) and Stela 5

Mapping the surface texture of stone monuments with Reflectance Transformation Imaging (RTI) now allows viewing them from multiple lighting angles in high resolution.

Today, RTI is widely used in archeology to document very shallow relief and shallow textures. This surface texture mapping technique reveals details on artifacts, paintings, and written documents on the scale of the thickness of a human hair.

Dr. Jason Jones, with a grant from England’s prestigious University of Warwick, used this RTI technology to examine the faces of the Izapa stelae. The RTI  viewer image of Stela 5 is a primary source scholars and interested parties can use to study its details.

RTI is an advanced capture technique that measures the texture of Stela 5 by tracking the movement of light over the stone carvings. This surface texture mapping technique was pioneered by HP Labs and further developed by Cultural Heritage Imaging. It combines many photos taken from a fixed camera position with different lighting angles. The result is a map of the Stela’s texture and the ability to see it lit from virtually any angle. RTI technology provides a powerful study aid to archeologists and researchers who want to understand what is on the surface of these monuments.