Abstract: An X-ray testing device for generating high-resolution geometric projections of a test object, includes a highly focusing X-ray source having: a rotary anode assembly formed by a rotatably mounted anode plate, an anode plate drive connected to rotate the anode plate and a rotational angle encoder detecting the rotation angle of the anode plate; an electron gun producing a focused electron beam; and an electron beam control unit having an electron beam deflecting unit and a control unit, the electron beam deflecting unit controlling the point of incidence of the electron beam generated by the electron gun on the anode plate. The control unit controlling the electron beam deflecting unit dependent on the detected rotation angle of the anode plate minimizing the positional change of the point of incidence on the anode plate relative to a reference point on a bracket holding the test object located in a fixed position.