Reflectance transformation imaging systems for ancient documentary artefacts

This paper discusses the interim results of the AHRC RTISAD project. The project has developed and tested a range of techniques for gathering and processing reflectance transformation imaging (RTI) data. It has also assembled a detailed understanding of the breadth of RTI practice. Over the past decade the range of applications and algorithms in the broad domain of RTI has increased markedly, with current working addressing issues such as large resolution capture, 3D RTI, annotation, enhancement amongst others. Capture of RTI datasets has begun to occur in all aspects of cultural heritage and elsewhere. This has in turn prompted the development of policies and methods for managing and integrating the large quantities of data produced. The paper describes these techniques and issues in the context of a range of artefacts, including painted Roman and Neolithic surfaces, examples of ancient documents in a variety of forms, and archaeological datasets from Herculaneum, Çatalhöyük, Abydos and elsewhere. The paper also identifies on-going software development work of value to the broad EVA community and proposes further enhancements