A method for copy retouching digital image data which contains a periodic pattern, includes calculating a distance vector D1 from the initially defined starting positions of a read mark and a write mark. The image data are then copied from the image points located under the read mark to the image points located under the write mark. In order to avoid a possible offset of the copied pattern area with respect to the surrounding pattern, a corrected distance vector D2 is calculated in such a way that the read mark and the write mark have the same phase position in relation to the periodic pattern. The method is particularly suitable for copy retouching of screened color separation data.