The calibration object is very simple, consisting of a rigid rod holding active or passive markers. The calibration process consists of three steps - acquiring a short sequence of the calibration object moving in the field of the cameras, detecting and tracking the markers automatically in all views, and simultaneously reconstructing the 3D trajectories of the markers and the camera parameters. The new software includes a graphical user interface (GUI) to allow even non-expert users to perform and validate a calibration. In the current version, user intervention is strictly limited to initializing the camera positions and orientations in a global reference coordinate system. MVCamera is tightlty connected to Blinky and MVVideo.