A method includes identifying at least first and second angles of rotation of the rotating gantry at which first and second pre-scans are acquired, wherein the first and the angles of rotation are different angles, acquiring data, via the imaging system while rotating the rotating gantry, only during a predetermined angular range about the first angle of rotation for a first plurality of rotations from the start to the end pre-scan positions and during the predetermined angular range about the second angle of rotation for a second plurality of rotations from the start to the end pre-scan positions, and reconstructing a first pre-scan based only on the data acquired during the predetermined angular range about the first angle of rotation and a second pre-scan based only on the data acquired during the predetermined angular range about the second angle of rotation.