A computer-implemented method is for artifact correction during a reconstruction of at least one slice image from at least one projection image. The at least one projection image includes a plurality of pixels, each pixel including a pixel value. The method includes determining at least one corrected projection image based on the at least one projection image via a computing circuit; reconstructing the at least one slice image based on the at least one corrected projection image; and providing the at least one slice image. The determining includes determining an average pixel value in at least one subarea of the at least one projection image, a correction value by multiplying the average pixel value by a scatter factor, and a plurality of corrected pixel values by subtracting the correction value from the plurality of pixel values. The corrected projection image includes pixels including the plurality of corrected pixel values.