Precise Measurement of Press Register.

It was found necessary to measure mechanical register between printing units of a new press independent of paper. A system of pick-ups together with an oscilloscope and a Polaroid Land Camera made it possible to isolate mechanical effects from those due to the printing process itself. Use of the system made possible a reduction in mechanical mis-register from .035 to .003 and led to a method of pre-inspecting a press without the necessity of printing. Circuit diagrams, progressive records and installation details will be given.