The present invention relates to a method for operating an x-ray apparatus for a creation (8) of a three-dimensional angiography of a body vessel segment (14), with a a) providing (1) of a three-dimensional reconstruction (10) of the body vessel segment (14) to a computer means of the x-ray device, with a b) calculating (3) a center line (15) by means of the body vessel segment (14) and determine (4) an axis of rotation (16) through the center line (15) by means of the computing device, with a c) registering (5) of the three-dimensional reconstruction (10) to the x-ray apparatus, with an e) evaluating (6) of the suitability of at least one exposure angle - pair with a first and a second exposure angle for the preparation (8) of the three-dimensional angiography with reference to an evaluation criterion of by means of the computing device and with an f) selecting (7) of a of the at least one evaluated exposure angle - pair for creating (8) of the three-dimensional angiography as a function of a result of the assessment, in order to improve production of the three-dimensional angiography.
