Abstract

This article offers a little review of the past few decades of prepress and color communication technology, and suggests a proposal for a new reference image file from which to derive all files, no matter the output. In doing so, it is suggested that an RGB workflow might be the best way to deliver consistent color reproduction.

A reference in color communication is typically based on a creative idea that comes from content originators—typically those who design, colorize, paint—or perhaps even create a fabric. Often it is the print buyer who, with art directors, is controlling and driving color references.

But, to make it short, an idea from the designer is communicated down the chain to art directors digitally to prepress and then to its final form—which can be output in many digital and/or print forms.

What have we used for color references to make sure that the designer’s expectations are met? How can we make sure that the dress that is seen in print or on a monitor is the true color?

One reference is physical. It has not been uncommon to bring physical samples to a press run—anything from textile samples, wood—you name it. These real, physical items are still carried to serve as color references for color critical reproduction. They are delivered as samples for retouching, or as reference pieces along with proofs.

If it is very critical, there are colorimetrical reference values that are considered.

If we look back a few years, there was one piece that effectively served as the color, contrast, modulation, sharpness...THE visual reference. It’s the photo slide. Art directors would even bring the original photo slide into the pressroom with a color accurate light table to see if there were any issues with the reproduction.

Since pretty much all image sources are now digital, we have lost such a reference. We have successfully advertised our digital world as an advantage, even to those print buyers who have lost their physical references.

After many years debating about who is the better artist—the retoucher or the printer—we have graduated to standards for reproduction, taking into consideration, print, ink, paper, and all the related measurements to achieve accurately some ISO standardized printing processes. As a result, powerful tools already exist, and related methodologies to reliably deliver the expected result in print.

Because output processes are now well organized, standardized and controlled we have seen how, at the end, the output has set the rules for all color communication. The creative process has become more and more forced to respect all rules emanating from the final output medium, from the standardization in color measurement, and the viewing and print (primarily offset). In essence, the color control process was completely reversed, starting from the output process and ending with the content creator—even if the final output condition is not yet known.

The impact of the standardization of printing processes and printing conditions has been very powerful. Many organizations, working groups and consultants developed exceptional tools that have helped to communicate color in a way that we had not seen before. There are FOGRA data sets, CGATS21 data sets, and Japanese data sets describing different flavors of standardized printing, among others. There are even more ICC profiles and profiling tools that have been derived from these characterized processes.

In the end, an actual print is still one snapshot of a final output of one of the analog output processes using a specific paper stock with a certain ink set based on a snapshot of standardized quality criteria, with local interpretations, using common measurement technologies and viewing cabinets, and of those analog printing conditions with all their restrictions. All of those standards and tools were created to support customer expectations with the lack of a real physical color reference. Where could we find such a reference? Is it my screen? Is it my GRACoL proof?

If it is my GRACoL proof, how accurate is this in an absolute comparison, if I look at the distribution of production paper tints (see graph)? With the actual M1 measurement condition all those paper tint measurements do spread even more than with the old M0 measurement.

If we look at this graph, it is obvious that, for example, GRACoL2013, might not be the best candidate. It is on the right, on the yellow side, compared to almost all the production papers in its class. Just imagine adjusting the paper tints from GRACoL to each of these papers!