ABSTRACT

Reflectance Transformation Imaging (RTI) is a non-invasive method of examination which can be used to document and visualize the surface texture of objects, including artworks. Through imaging an object under different directions of illumination, topographical maps of a low relief surface can be produced, which when further processed can be used as an interactive visual aid. This paper summarizes the current state of research on micro-RTI, and presents an investigation into a micro-RTI system comprised of a digital microscope and miniature lighting array dome, which was originally developed to study small areas of surface texture. The article reviews the techniques required to adequately use the micro-RTI, and evaluates the system’s use as a practical tool for conserving and documenting modern and contemporary easel paintings. This was determined by evaluating its data processing, ability to accurately document test panels and case study paintings, and comparing it with alternative documentation methods of standard microscopy and laser scanning. It was found that micro-RTI is a useful tool for modern and contemporary paintings and their often complex and/or delicate surfaces, where subtle surface alterations can result in visually distracting features.

摘要

反射率转换成像（RTI）是一种非侵入性的检查方法，可用于记录和可视化包括艺术品在内的物体的表面纹理。通过在不同照明方向上对物体成像，可以生成低浮雕表面的地形图，当对其进行进一步处理时，可以用作交互式视觉辅助。本文总结了对微型RTI的研究现状，并提出了对由数字显微镜和微型照明阵列圆顶组成的微型RTI系统的研究，该系统最初是为研究小范围的表面纹理而开发的。本文回顾了充分使用micro-RTI所需的技术，并评估了该系统作为保存和记录现代和当代画架画的实用工具的用途。这是通过评估其数据处理能力，准确记录测试面板和案例研究画图的能力并将其与标准显微镜和激光扫描的其他记录方法进行比较来确定的。已经发现，micro-RTI是用于现代和当代绘画及其通常复杂和/或细腻表面的有用工具，其中细微的表面变化会导致视觉上分散注意力的特征。