A method for correcting image artifacts is proposed. The artifacts occur as a result of an anti scatter grid connected rigidly to an x-ray detector in recording three-dimensional image datasets. Two-dimensional projection images of an object are recorded from different recording geometries for reconstruction the three-dimensional image dataset. A calibration image is recorded for each recording geometry. An average image from all recorded calibration images is established. Subtraction images are established by subtracting the average image from the corresponding calibration images. Noise is removed from the subtraction images. The subtraction images and the average image are stored. A correction image is established for each recording geometry by addition of the subtraction image assigned to the recording geometry and of the average image and is used for correcting the projection image.