1. An automatic method for determining the geometric center of an element having a known peripheral shape of double symmetry comprising: selecting a trial center of an image of said element and defining a plurality of sectors radiating from said trial center and ecompassing all of at least a preselected portion of said element image; determining which ones of a locus of points overlie said image, said locus of points consisting of a number of spaced points along a line running through all of said sectors and having a predetermined relationship to said trial center; comparing the number of points that overlie said image in each sector with the number of points overlying said image in each of the other sectors; ascertaining whether said comparison is the same as a predefined comparison that exists when the trial center is the geometric center of said element; and if said comparison does not equal said predefined comparison, relatively moving said trial center with respect to said geometric center and repeating said selecting, determining, comparing and ascertaining steps.