A method is disclosed for generating image data of an object under examination from X-ray projection data of the object under examination, wherein, before a reconstruction of the image data, the X-ray projection data are subjected to scattered radiation correction on the basis of scattered radiation measured values. Here, the scattered radiation measured values are initially subjected to an extra-focal radiation correction before being used for the scattered radiation correction. A projection data processing device is also disclosed for carrying out a method of this kind and an X-ray system, in particular computed tomography system, with a projection data processing device of this kind.
