To move the light position in the interactive RTI, make sure the lightbulb icon in the bottom right corner is highlighted rather than dark then click and drag across the viewer.
To pan around the image, turn the lightbulb icon off, and click and drag across the viewer.
Use the layers icon to enable enhanced views of the RTI, including diffuse and specular (mathematical enhancements that remove colour and increase contrast), and normals (a false-coloured static view of the surface profile).
Reflectance Transformation Imaging can be carried out with a minimum of equipment. This view of a pot sherd was taken using a simple LED torch and a basic DSLR camera on a horizontal-arm tripod. You can see that the lighting of the image is not evenly cast, due to variation in the torch's light coverage, and variation in distance of the torch from the subject, but the result still provides an interactive view of the sherd, allowing better study of its construction and decoration.
A pot sherd from Syria, showing decoration created by pressing plied cord into the clay surface before firing.