Several components of prepress and press systems can be integrated to
produce a lithographic press which achieves a high degree of
CIP3-compliant prepress workflows can be captured in Print Production
Format (PPF) files. The PPF file is accessed by all prepress devices. Each
device adds its output to the file and the result contains digital image
and ink key data.
Job schedulers add substrate size and thickness information and query
the press for maintenance and error status. The resulting job ticket is
then passed to a press management system where the press operator controls
Press setup and makeready is performed by a control system on the
press. Integral features include the ability to automate cleanup from the
previous job, set digital ink keys and ink up for the current job, change
plates automatically and set ink film thickness. If all parameters are
properly set, the first sheet pulled can be checked by the operator.
Once the operator accepts the sheet, its color densities can be scanned
by a spectral densitometer. These color standards can be maintained
throughout the press run by closed loop color control by repeated
automated scanning and ink key adjustments.
Measurements and statistics can be taken and stored at any point along
the automated processing train for offline production management.
Source: Graphic Arts Monthly, Feb 2000, p. S2-S8