Whereas the CT image can be acquired in a single revolution, the CSCT image acquisition may require several revolutions. According to an exemplary embodiment of the present invention, a CT/CSCT apparatus may be provided which uses CT data acquired during the first revolution to optimize acquisition parameters for the subsequent revolutions. Furthermore, projection data acquired with a pre-scanner may also be used for determining current modulation or setting an optimum voltage for the subsequent CSCT scan.