1. A method of manufacturing at least one wafer or chip, comprising: obtaining image data of the at least one wafer or chip; correcting the image data to remove normal variation within the image data; comparing the corrected image data to image data for at least one other wafer or chip to determine whether the corrected image data for the at least one wafer or chip shows a defect or anomaly beyond that of the normal variation; and placing the at least one wafer or chip into a category of fabrication based on the comparison.