A system and method for automatically focusing imaging devices on an imaging set employs at least one tracker and two or more tracking markers, each tracking marker having an identification means and a tracking pattern. The tracking markers are configured for attaching to the imaging devices and to corresponding subjects to be imaged. A tracker gathers image information of the imaging set and provides it to a controller, which compares the image information to predetermined stored information about the tracking patterns of the various tracking markers. The tracking markers are identified and their three- dimensional positions determined. The distances between the imaging devices and the subjects are determined and the distances between the imaging devices and the subjects are calculated. This provides the focus setting information for communication to the imaging devices. The tracking patterns may have no rotational symmetry, allowing the orientation of subjects to be determined.