# Tracking Bar Coordinate System The OptiTrack Duo/Trio tracking bars are factory calibrated and there is no need to calibrate the cameras to use the system. By default, the tracking volume is set at the center origin of the cameras and the axis are oriented as shown in the following image (Z forward, Y up, X left):

If you wish to change the location and orientation of the global axis, you can use the Coordinate Systems Tool which can be found under the Tools tab. ## Coordinate Systems Tool *** When using the Duo/Trio tracking bars, you can set the coordinate origin at desired location and orientation using a calibration square. Make sure the calibration square is oriented properly. Adjusting the Coordinate System Steps: 1. First set place the calibration square at the desired origin. 2. \[Motive] Open the Coordinate System Tools pane under the Tools tab. 3. \[Motive] Select the Calibration square markers from the Perspective View pane 4. \[Motive] Click Set Set Ground Plane button from the Coordinate Systen Tools pane, and the global origin will be adjusted.