WORKFLOW: GRACoL Finds Its Balance

Print has remained a compelling advertising medium even in the face of new digital competitors, and advertisers have been a driving force behind this improvement. Ad buyers led the charge for the printing industry's first modern standard in 1974, when an ad-hoc committee formed to discuss ways to improve the consistency of print reproduction among the growing legion of web offset printshops. This group coined the moniker “Specifications for Web Offset Publications” in 1976, leading to the first set of guidelines bearing the SWOP name a year later.

A process guideline that brought a measure of control to a wildly inconsistent marketplace, SWOP defined acceptable ranges for density and dot gain along with a set of target CMYK hues. Following SWOP's success in the web offset marketplace, GRACoL (General Requirements for Applications in Commercial Offset Lithography) emerged as an equivalent sheetfed standard. Once again, the emphasis was on controlling process variation within an acceptable range.

Allowing variation makes it easier to hit the standard, but that same leeway hinders the creation of a definitive proof. Digital proofing and color management introduced a level of precision that cries out for an exact definition of “quality offset printing.”

Recognizing this need, industry group IDEAlliance undertook the onerous process of measuring and averaging ISO 12647-2 print run data from several high-quality sheetfed printing firms.

The results of this endeavor are documented in the ANSI Technical Report (TR) 006 for GRACoLprinting on Grade 1 coated paper, undoubtedly the most precise characterization of sheetfed offset print quality yet produced. The spectral color data captured by IDEAlliance not only clarifies the traditionally accepted density, tone value increase (dot gain) and print contrast values, but it created a definitive picture of how CMY gray balance changes from highlight to shadow. TR 006's more accurate characterization (as codified in the new GRACoL2006_Coated1 ICC profile) means better results from color management systems.

In essence, while previous specifications have defined the acceptable limits of key processes, GRACoL can now define the proper visual appearance of both contract proofs and presswork. No one can argue the value of more accurate data, yet the publication of GRACoL's seventh version has inspired a great deal of controversy. “When someone claims they can make printing to the proof easier, people are naturally skeptical,” notes Don Hutcheson, color management guru and chair of IDEAlliance's GRACoL committee.

Much of the debate has focused on the G7 Method, defined as “the calibration and press control process proposed in the new GRACoL specification.” This approach emphasizes gray balance over traditional objective measurements such as density and dot gain, and with good reason: Nothing upsets a print buyer more than a color cast! By maintaining gray balance, G7 advocates proclaim, the job's visual appearance will remain acceptable even if ink densities fluctuate.

Traditionalists counter that press operators are ill-equipped to make judgments based on the CIELAB measurements used to assess gray balance; pressroom consultants worry operators won't notice mechanical problems if dot gain and print contrast measurements are abandoned.

While G7 consultants adjust to real-life concerns, press manufacturers are keenly interested in automating the production of acceptable color with a “G7 button” to maintain neutral grays. How's that for enthusiastic support?