Reflectance transformation imaging at a microscopic level: A new device and method for collaborative research on artifact use-wear analysis

This paper outlines the technical foundation and operational principles of Reflectance Transformation Imaging (RTI) technology, emphasizing its pivotal role in archaeological artifact analysis and documentation. It reflects on RTI studies to demonstrate its significant impact in providing detailed multi-directional insights, particularly in use-wear analysis. A comparative assessment of images captured through different techniques reveals that Microscopic-RTI delivers exceptionally comprehensive information, markedly enhancing the visual representation of active tool surfaces. These findings accentuate the substantial value of Microscopic-RTI in research and documentation for use-wear analysis, affirming its effectiveness as an integral and complementary tool alongside other imaging technologies. This study demonstrates that RTI can successfully examine features at a microscopic level. Specifically, it evaluates various microscopy-scale photography methods, focusing on the ‘highlight’ method (H-RTI) for documenting sub-millimetre details, such as those examined in use-wear analysis. The study investigates the implementation of Microscopic-RTI, a novel RTI method that utilizes a microscope, for the exaination and documentation of archaeological and experimental use-wear on stone tools. This technique enables the capture of fine surface details that may not be identifiable through ordinary photography and microscopy. Given the prohibiting cost of an RTI dome, this study proposes the cost-effective make-shift construction of a simile dome and reviews how it functions along with appropriate RTI programs for documentation of use-wear, hoping to propel the subdiscipline of use-wear analysis to more accurate and objective documentation and interpretation of use-wear which can be widely shared and used.