Aligning Angular Offsets

  • To correct for the small angular misalignments between tracker and camera:
  • Load the FBX file that correlates to the Intersense fidicual locations of the stage. Instructions for generating this file are here.
  • Check that the right lens calibration file is selected, the zoom and focus are correctly lined up, and that the correct sensor size is selected.
  • Check that the lens controller has not slipped any teeth when starting up; if necessary power cycle the lens controller and make certain of this. Small error in barrel position lead to very large errors in virtual scene position.
  • Rotate the Intersense camera to 45 degrees from horizontal, and adjust the Intersense configuration panel”s pitch setting to 45 degrees.
  • Make sure that the Airtrack”s drift compensation is updated.
  • Point the camera up toward the ceiling so that the fiducials are in view of the camera.
  • Set all of the Coordinate System offsets to 0. (The Tracker to Camera offsets should be the normal distance from the Intersense to the camera sensor.)


  • The fiducials should line up pretty closely to the CG cones.
  • If they are offset, adjust the Tracker to Camera Offset panel’s Pan and Tilt settings to line them up. Note — this should be a small number of degrees; around 2-3 degrees in the Pan, and less than a degree in the Tilt. If it takes more than a degree in Tilt, look at the mounting bracket to make sure it is seated on the matte box rails, at a right angle to the matte box rails.
  • Pan the camera around, and move it back and forth. The fiducials should stay more or less connected to the CG cones. There will generally be several pixels of error on large pan moves, and less error on translation type moves such as a dolly move or a crane move.