a registration target for printing on a web or sheet includes a pair of juxtaposed orthogonal arms , at least one of which extends lengthwise along the web . one or more tabs projects perpendicularly from each arm but only at one edge thereof . the widths of the arms and tabs substantially correspond to the stroke width of the lines and characters being printed on the web and the length of each tab is a multiple of that stroke width . by observing the orientations of the tabs and the amounts by which they project beyond one another of the targets printed by a series of print cylinders in a press , one can immediately discern the directions and amounts in terms of stroke width of any registration errors .