In the acquisition of an image series with an x-ray image acquisition that has an x-ray C-arm rotatable around a center point, movement of the patient table is updated so that table is brought into a specific position calculated relative to the angle position of the x-ray C-arm. This position of the patient table is determined as follows. An envelope is established and a point is established that is the center point of a region of interest. In each position of the patient table that matches the position of the x-ray C-arm, the flat panel detector is perpendicular to a line emanating from the point and simultaneously contacts (is tangent to) the envelope. The region of interest is thereby optimally imaged in the image series so that a good 3D reconstruction can be obtained.