A medical imaging system includes a gantry, a display device, and a control circuit. The gantry includes detector arms circumferentially spaced apart along a perimeter of a bore and radially movable towards and away from a subject. The control circuit generates a subject shape outline of the subject within the bore based on obtained contour image data of the subject. The control circuit determines designated scan positions of the detector arms based on the subject shape outline. The control circuit displays the subject shape outline on the display device within a gantry visualization that is a graphical representation of the gantry showing the bore. The control circuit displays a set of graphical detector arms on the display screen within the gantry visualization. The graphical detector arms are displayed at the designated scan positions relative to the gantry of the gantry visualization to show a subject-gantry geometric relationship.