RTI is a technology created by Cultural Heritage Imaging, a nonprofit organization dedicated to advancing digital capture and documentation practices in cultural heritage institutions. CHI offers free downloads of RTI software, and provides online and on-site training.

Images for RTI can be captured in two ways; either with a light source that is moved by hand as shown here during a training session at Yale:

Or with a dome containing many stationary light sources, each one of which flashes in succesion during a series of photographic captures.

Yale's Center for Conservation and Preservation uses an RTI dome in their imageing lab.