What is GRACoL? Most simply, it stands for “General Requirements for Applications in Commercial Offset Lithography”. To elaborate a bit more, it deals with the ability to have consistency in offset Lithography. This consistency is the result of being able to establish some common ground amongst a somewhat volatile printing arena. The goal is to establish a set of requirements that offset printers can easily adhere to.
IDEAlliance and Standards
IDEAlliance specifications and guidelines are not standards, though many in the industry persist in the misconception that they are. They are not and have never been developed to compete with existing standards and, in fact, are built upon and rely on what are called “Core Technology Standards,” most of which are developed by ISO—the International Standards Organization—which governs all industries, including printing.
History of GRACoL
GRACoL started in 1996 when a group of volunteers from various facets of the graphics arts industry came together to develop a task force that was later christened the IDEAlliance. Their goal was to conceive a usable set of guidelines and specifications for the commercial offset industry.
In 1997, the first GRACoL publication, version 1.0, was released. Later tests were conducted at several printing locations with the goal of characterizing optimized commercial offset printing on paper grades #1 and #2, using certified inks printed at 175-line. Those sheets were considered representative of optimized printing quality for GRACoL and became the basis of GRACoL 6—published in 2002.
These printing aim points were submitted to CGATS on January of 2004 and were termed Data Technical Report 004 (DTR 004).
DTR 004 engendered a great deal of interest in the printing industry and also spurred further testing evaluations. Industry authorities deemed this first attempt unacceptable, so GRACoL went back to the drawing board to develop not only new aim points for commercial printing but also a new process that would assure a closer visual match between the creative and the finished product on press. That effort resulted in GRACoL 2007, and its revolutionary companion process of press calibration called G7.
The most compelling aspect of GRACoL 2007 is that it was developed as a result of a significant number of real press runs, collaboration between our industry’s top experts, and modern technology that was not available at the time of the first GRACoL efforts. The new approach is based on a visual match between proof and output on press, always considering first how printing looks to the human eye.
The new focus on measuring gray scales rather than individual colours is a break from traditional printing practices. Nevertheless, it is more effective, faster, and easier to apply. It is important to note that GRACoL does not rule out traditional measurements for process control.
GRACoL and Colour Management and Today’s Workflows:
GRACoL is based on current technology, and its development parallels developments in other areas of our industry. Colour management and ICC colour workflows are based on colorimetric data rather than densitometry aims such as dot gain. GRACoL has embraced the maturity of colour management and recognizes that it is an integral part of the process that moves from digital photography, to image retouching, to soft-proofing, to ink-jet proofing, to custom press profiling. For the first time, we have the ability to work backwards from the press. Thanks to GRACoL, we can now connect the dots from capture to print, allowing everyone in the chain to fully exploit the tools of colour management.
Angus Pady is the president of Digital Solutions. Complete colour control from desktop to press. T: 905.764.6003