Scanning artifacts; those are moiré patterns caused by the interaction of the scanner’s (or camera’s) color filter array with fine detail in the source image (s

Scanning artifacts; those are moiré patterns caused by the interaction of the scanner’s (or camera’s) color filter array with fine detail in the source image (stippling or striping or whatever the original image did to convey shading in a two-color print). https://www.imatest.com/solutions/moire/ https://www.imatest.com/solutions/moire/