A method of detecting an object comprising: (i) calibrating a staging system, the staging system including a mobile platform, a target frame mounted to the mobile platform for pivotal movement about a horizontal pivot axis between a first pivot angle (Fig. 5) and a second pivot angle (Fig. 6), a beacon on the target frame, and a target frame mirror attached to the target frame, the method including: generating a stage calibration light beam; reflecting the stage calibration light beam from the target frame mirror; pivoting the target frame about the horizontal pivot axis between the first pivot angle and the second pivot angle relative to the mobile platform; detecting first and second locations (Fig. 7B; Fig. 7C) of the stage calibration light beam after the stage calibration light beam is reflected from the target frame mirror when the target frame is in the first pivot angle and in the second pivot angle respectively; determining, based on the first and second locations, a value representing an orientation of the target frame mirror relative to the horizontal pivot axis; and adjusting, based on the determination of the value representing the orientation of the target frame mirror, the orientation of the target frame mirror relative to the target frame so that the target frame mirror is more normal to the horizontal pivot axis; characterized in that the method further comprises: (ii) using the staging system to generate a stage-based location of the beacon, including: generating a stage positioning light beam; reflecting the stage positioning light beam from the target frame mirror; detecting a location of the stage positioning light beam after the stage positioning light beam is reflected from the target frame mirror (20; 22); and determining a stage-based location of the beacon on the target frame based on the stage positioning light beam (23; 80). (i) calibrating a staging system, the staging system including a mobile platform, a target frame mounted to the mobile platform for pivotal movement about a horizontal pivot axis between a first pivot angle (Fig. 5) and a second pivot angle (Fig. 6), a beacon on the target frame, and a target frame mirror attached to the target frame, the method including: generating a stage calibration light beam; reflecting the stage calibration light beam from the target frame mirror; pivoting the target frame about the horizontal pivot axis between the first pivot angle and the second pivot angle relative to the mobile platform; detecting first and second locations (Fig. 7B; Fig. 7C) of the stage calibration light beam after the stage calibration light beam is reflected from the target frame mirror when the target frame is in the first pivot angle and in the second pivot angle respectively; determining, based on the first and second locations, a value representing an orientation of the target frame mirror relative to the horizontal pivot axis; and adjusting, based on the determination of the value representing the orientation of the target frame mirror, the orientation of the target frame mirror relative to the target frame so that the target frame mirror is more normal to the horizontal pivot axis; characterized in that the method further comprises: (ii) using the staging system to generate a stage-based location of the beacon, including: generating a stage positioning light beam; reflecting the stage positioning light beam from the target frame mirror; detecting a location of the stage positioning light beam after the stage positioning light beam is reflected from the target frame mirror (20; 22); and determining a stage-based location of the beacon on the target frame based on the stage positioning light beam (23; 80). generating a stage calibration light beam; reflecting the stage calibration light beam from the target frame mirror; pivoting the target frame about the horizontal pivot axis between the first pivot angle and the second pivot angle relative to the mobile platform; detecting first and second locations (Fig. 7B; Fig. 7C) of the stage calibration light beam after the stage calibration light beam is reflected from the target frame mirror when the target frame is in the first pivot angle and in the second pivot angle respectively; determining, based on the first and second locations, a value representing an orientation of the target frame mirror relative to the horizontal pivot axis; and adjusting, based on the determination of the value representing the orientation of the target frame mirror, the orientation of the target frame mirror relative to the target frame so that the target frame mirror is more normal to the horizontal pivot axis; characterized in that the method further comprises: (ii) using the staging system to generate a stage-based location of the beacon, including: generating a stage positioning light beam; reflecting the stage positioning light beam from the target frame mirror; detecting a location of the stage positioning light beam after the stage positioning light beam is reflected from the target frame mirror (20; 22); and determining a stage-based location of the beacon on the target frame based on the stage positioning light beam (23; 80). generating a stage positioning light beam; reflecting the stage positioning light beam from the target frame mirror; detecting a location of the stage positioning light beam after the stage positioning light beam is reflected from the target frame mirror (20; 22); and determining a stage-based location of the beacon on the target frame based on the stage positioning light beam (23; 80).