1. A method for generating a magnetic resonance (MR) angiography image, comprising: operating an MR scanner, while a patient is situated therein, to obtain a plurality of successive two-dimensional slice images that cover an examination volume of the patient along an axial direction slice-by-slice, using a time-of-flight angiography MR data acquisition sequence; providing said plurality of slice images to a processor and, in said processor, dividing said plurality of slice images into respective groups with each group comprising a predetermined number of consecutive slice images along said axial direction; in said processor, determining a maximum intensity projection image for each group; and in said processor, determining diagnostic angiography images as the respective maximum intensity projection images for the respective groups, or dependent on the maximum intensity projection images for each group, and making said diagnostic angiography images available in electronic form from said processor as respective data files.