Abstract: The present invention relates to a device for determining a focal spot size, and/or a pulse duration, and/or an X-ray intensity for an X-ray pulse for a sequential X-ray imaging apparatus, the device (1) comprising: a receiving unit (2); a mode determining unit (3); and a transmitting unit (4); wherein the receiving unit (2) is configured to receive a status signal (24) indicating a motion status of an object of interest (7); wherein the mode determining unit (3) is configured to determine an acquisition mode based on the indicated motion status of the object of interest (7); wherein the acquisition mode defines a focal spot size, and/or a pulse duration, and/or an X-ray intensity for an X-ray pulse for a sequential X-ray imaging apparatus (10); wherein the focal spot size, and/or the pulse duration, and/or X-ray intensity for an X-ray pulse are adapted to the motion status of the object of interest (7); and wherein the transmitting unit (4) is configured to provide a mode signal indicating the determined acq