A computer-implemented method for calibrating a motion detection system working according to a motion detection technique and configured for detecting a motion of an object during medical imaging by means of a medical imaging system, the computer-implemented method comprising an automatic calibration process for determining at least one motion threshold for said object motion detection system, said calibration process taking place for said object being in a position and place allowing its imaging by said medical imaging system the calibration process comprising: a. using the motion detection system working according to said motion detection technique for repeatedly acquiring motion detection data enabling object motion detection and using a motion quantification system working according to a motion quantification technique for repeatedly acquiring motion quantification data enabling object motion quantification; b. analyzing the motion quantification data for determining if said object was mobile or immobile; and i. if said object was immobile, then using the motion detection data for determining an object motion threshold for the motion detection system wherein said object motion threshold is determined by statistical analysis of the motion detection data; ii. if said object was mobile, then correlating the motion quantification data and the motion detection data for determining an object motion threshold for the motion detection system, wherein the threshold is determined from motion detection data correlated to motion quantification data characterizing an object motion that remains within a predefined tolerance value. a. using the motion detection system working according to said motion detection technique for repeatedly acquiring motion detection data enabling object motion detection and using a motion quantification system working according to a motion quantification technique for repeatedly acquiring motion quantification data enabling object motion quantification; b. analyzing the motion quantification data for determining if said object was mobile or immobile; and i. if said object was immobile, then using the motion detection data for determining an object motion threshold for the motion detection system wherein said object motion threshold is determined by statistical analysis of the motion detection data; ii. if said object was mobile, then correlating the motion quantification data and the motion detection data for determining an object motion threshold for the motion detection system, wherein the threshold is determined from motion detection data correlated to motion quantification data characterizing an object motion that remains within a predefined tolerance value. i. if said object was immobile, then using the motion detection data for determining an object motion threshold for the motion detection system wherein said object motion threshold is determined by statistical analysis of the motion detection data; ii. if said object was mobile, then correlating the motion quantification data and the motion detection data for determining an object motion threshold for the motion detection system, wherein the threshold is determined from motion detection data correlated to motion quantification data characterizing an object motion that remains within a predefined tolerance value. <EOS>