Fuhrmann, AntonSchmalstieg, DieterPurgathofer, WernerJ. D. Mulder and R. van Liere2014-01-272014-01-2720003-211-83516-41727-530Xhttps://doi.org/10.2312/EGVE/EGVE00/003-012Augmented Reality overlays computer generated images over the real world. This requires precise knowledge of the viewing projection of the headmounted display (HMD) and its position. Most of the previously published methods are complicated or use special equipment for the calibration process. We present a collection of calibration methods usable for fast and easy calibration of camera parameters, object/camera to tracker transformations, and image rectification, which do not need additional instrumentation or complicated procedures. They are applicable for both see-through and videobased HMDs and have already been successfully implemented in the Studierstube collaborative augmented environment.