Product

Platform

Server: Data General or Dell all; Client: PC or Macintosh

Operating system

Server: Windows NT or 2000; Client: Windows or Macintosh

Error

Symptoms

***Applies to Prinergy Connect, Powerpack, Direct, Satellite, depending on installed configuration.***

Overprint is enabled for a grayscale object in the desktop publishing application, for example, QuarkXPress, but when the composite PostScript is refined and RIPed, the gray object knocks out the other separations.

Cause

If knockout is specified, then the object should be rendered white on all separations for which it has zero color content. If overprint is specified, then all zero-content separations are left untouched by the object.

In the composite PostScript generated by the desktop publishing application, gray objects are almost always represented in the /DeviceGray colorspace. The Adobe RIP will not overprint objects that are /DeviceGray even if overprint is enabled for that object.

Solution

In Prinergy, enable the Color Convert in the Refine process plan.

The color converter will convert gray objects into a colorspace that the Adobe RIP will overprint as expected. For more information about overprinting see Prinergy Online Help.

QuarkXpress places a white box set to knock out behind the image, so even if the image is set to overprint, the result is a knock out. You must use PitStop to delete the white box for overprint to work correctly. This is a bug in QuarkXpress.

Permanent fix:

See also

Keywords

RIP

Technical contact(s)

Rob Prior

Submitted by

Simon Chen

Date submitted