Lithographic Precontrol.

This paper will deal with the types of controls we have established using the technical data available to ensure maximum repeatability from proof to proof or from proof to press. Areas to be covered will include plate step wedges, equivalent neutral density, and star and slur targets for 150 to 200 line screens. Also covered will be densitometry readings plotting of more than one proof, press ink rotation, register marks, proofing and printing plates.