Reflectance Transformation Imaging

RTI is a newer imaging technique that creates virtual three-dimensional digital surrogates that are controlled interactively. This technique is based upon the synthesis of images of an object in a fixed position. All images (approximately 50) are acquired from a single fixed camera position. A light source is repositioned at a constant radius from the subject, and therefore creates a hemisphere of positions. The final processed file determines all possible light positions within the virtual hemisphere, in addition to those in images. The final image initially looks like a flat photograph, but it is actually the documentation of the subject’s surface interaction under the changing light positions.

By moving a mouse (or other pointing device), one can control the light direction, zoom in and out, and select enhancement options that increase sharpness and contrast and even change surface properties.

Click on the image to the right to view a video of the interactive RTI file.