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 a 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 direction; in said processor, determining a maximum intensity projection image for each group using the slice images of that group; and in said processor, determining at least one diagnostic angiography image for each group by determining a correlation measure for each slice image in a respective group with regard to the maximum intensity projection image that was determined for that group, and thereby obtaining a plurality of correlation measures for each group, and determining said at least one diagnostic angiography image for the respective group dependent on an evaluation in said processor of the respective correlation measures for the slice images in that respective group and making the respective diagnostic angiography images for each group available in electronic form from said processor as respective data files.