What is registration black?

Registration black is a special swatch set to 100 percent of all four CMYK plates at once. It exists so that crop marks and registration marks print on every plate for press alignment, and it should never be used for artwork.

• Made of 100 percent cyan, magenta, yellow, and black, totaling 400 percent ink.
• Meant only for crop marks and registration marks, not text or fills.
• That much ink can smear, offset onto other sheets, and cause misregistration.
• For real black in your design, use rich black or 100 percent K instead.