Abstract: In a tomography-capable imaging examination apparatus, and an operating method therefor, an operator first determines a desired scan volume of the examination subject, and then, controlled by the computer device, a raw data set, having data allocated to different directions, is acquired in the scan volume. For planning the subsequent calculation of the resulting image—keeping pace with the scan or immediately after its termination—the computer device calculates and displays a graphic overview representation of the subject of examination from the raw data. The overview representation contains three-dimensional information about the scan volume. In this volume, the operator selects a diagnostically relevant region of representation. Using an image calculation algorithm, the computer device calculates a diagnostically relevant resulting image in the selected region of representation. The quantity of data thus is reduced immediately upon its origination.