1. In a workpiece manipulating system having a manipulator with jaw means for engaging a workpiece on a work area, said manipulator having sensor means for indicating the coordinate position of said jaw means in a first coordinate system, and an optical image converter positioned to view an image on the work area and generate a signal in reponse thereto, analyzing means operatively coupled with said converter for computing the coordinate position of the centroid of said image in a second coordinate system, a method for translating coordinate positions from said second coordinate system to coordinate positions in said first coordinate system comprising the steps of: placing a target in said jaw means, moving said jaw means and target between a predetermined number of points across said work area, determining the coordinate position of said target in both of said coordinate systems at each of said points, computing transformation factors for translating any coordinate position on said work area in said second coordinate system to the same coordinate position on said work area in said first coordinate system, and storing said transformation factors.