RIDGEFIELD PARK, N.J. — Agfa Corp. held a press briefing at its headquarters here in July to give journalists a peek at the new digital proofing and color management systems it plans to unveil this month at Print ’01 in Chicago.

Focusing on its ability to provide a turnkey solution, Agfa has expanded its family of Sherpa proofers to include two new engines, and has updated its ColorTune Pro color management system and its new Quality Management System. Agfa also will introduce Agfa Open Access, which gives users the ability to integrate the Sherpa into Harlequin Delta and Scitex Brisque workflows.

Ink-jet technology update

Deborah Hutcheson, senior marketing manager for workflow and color systems at Agfa Graphic Systems, discussed the difference between the two types of ink-jet proofing technologies — continuous tone and drop-on-demand.

Agfa will give demonstrations of two new 
Sherpa proofing engines at Print ’01 this 
month in Chicago.
Photo courtesy of Agfa

Continuous tone proofers provide high quality and a variable dot, but they are slow, have high ink consumption, high maintenance, poor dot control, and a limited resolution of only 300 to 600 dots per inch, she said.

There are two kinds of drop-on-demand ink-jet technology — thermal and piezo.

With thermal drop-on-demand, the ink is heated to create a vapor bubble, and pressure forces the ink to drop out of the nozzle. The chamber cools, creating a vacuum that draws new ink into the firing chamber, so there is a constant heating and cooling process going on.

Thermal drop-on-demand is faster than contone, but the ink being used must be heat resistant. With thermal, the drop size is large and inconsistent, between 50 and 60 microns. The maximum resolution is 600 dpi. Another disadvantage of thermal is its high ink consumption. Thermal uses about 40 percent more ink than the drop-on-demand piezo technology, according to Hutcheson.

With piezo technology, a crystal flexes when an electric current is applied, and ink is forced out of the nozzle. Piezo allows better control over the shape and size of the ink drop, and provides a much smaller drop vs. thermal, at a much higher resolution of up to 1,440 dpi. The equipment and consumables used with piezo technology are less expensive, and the ink is optimized for different absorption and drying properties.

All the proofers in the Sherpa family use the drop-on-demand piezo electric ink-jet technology.

“The Agfa Sherpa solution offers the high resolution only possible with piezo technology,” Agfa Graphic Systems President Robert Stabler said at the seminar. “It delivers contract color, quality control, workflow integration and system compatibility. It offers the highest level of productivity currently on the market, application flexibility, it is cost effective, and you need only one type of proofer to handle every proofing need.”

The history of Sherpa

The first two Sherpa engines were introduced in the United States at Graph Expo 1999 — the Sherpa 2, which is an imposition proofer, and the Sherpa 43 for contract or color proofing.

The Sherpa 2, which is most applicable for newspapers, has two resolutions — 360-by-360 dpi or 720-by-720 dpi. The four-color proofer can run in two modes, as a single-sided automated or as a dual-sided manual.

“The No. 1 objective for imposition proofing is speed. You want to get the job out as fast as possible,” Hutcheson said.

Shortly thereafter, Agfa brought out the 62-inch Sherpa contract proofer, and at Graph Expo 2000 introduced the Sherpa 24. All three contract proofers — the Sherpa 24, 43 and 62 — are multi-density, six-color systems, using the standard CMYK inks, plus a light magenta and light cyan. The CCMMYK multi-density inks are designed to provide improved ink blending, a wider color gamut, smoother gradations, finer details, smoother flesh tones and better color matching.

At Print ’01 in Chicago this month, Agfa will give live demonstrations of the new SherpaMatic, and the high-resolution Grand Sherpa.

Based on the Sherpa 43, the SherpaMatic is an automated two-sided proofing device. It provides unattended operation and has a built-in alignment mechanism. Agfa expects commercial sales of the SherpaMatic by next month.

Also new for Print ’01 is the Grand Sherpa, offering resolutions up to 1,440-by-1,440 dpi. The Grand Sherpa will come in three widths — 50-inch, 64-inch, and 87-inch for very large format proofing. The Grand Sherpa is eight-color capable, with 16 print heads and a variable dot size.

Of interest to newspapers, the Grand Sherpa could be run as two sets of CMYK for very high speed imposition proofing. In a resolution-to-resolution comparison, the Grand Sherpa is three times faster than anything currently on the market, Hutcheson stated. Commercial sales of the Grand Sherpa are expected by the fourth quarter.

What is color management?

Color management not only gives the ability to improve color, but also the ability to reduce waste and improve productivity through automation.

Following the digital proofing and color management presentation, Agfa employees and a group of journalists toured the Technology Learning Center, which was recently moved to the company’s headquarters, during its grand opening.
Photo by Lisa Larson

“Before we talk about what color management is, it’s important that we all understand what color management is not — and there’s a lot of misconceptions about it in the industry,” Hutcheson said. “Color management doesn’t make all the color look alike. It doesn’t eliminate non-reproducible colors. It is not a color correction tool, and more importantly, it is not a quality control tool.

“If you don’t have good quality control within your shop, color management is not going to be effective because you can’t color profile something that’s a moving target. You’ve got to have a good, stable work environment,” Hutcheson stated.

That is why every Sherpa comes with a ColorTune color management system, the new Quality Management System and a dedicated X-Rite DTP 41 spectrophotometer. A Sherpa package also includes an Apogee Series 2 PDF proofing raster image processor, the ink set, one roll of media, one custom profile and technical support.

As one of the founding fathers of the International Color Consortium, Agfa, along with Adobe Systems Inc., Microsoft Corp. and Apple Computer, got together and developed an open, vendor-neutral, cross-platform color communications standard. ICC profiles are used to communicate the color gamut of one device to another.

A color gamut is the range of colors that a device can reproduce. The color gamut of a monitor is greater than the color gamut of a proofer, and the color gamut of a proofer is greater than the color gamut of a press.

“When you have color-managed workflow, you’re essentially defining the color behavior of each of the devices within that workflow using a device-specific ICC profile,” Hutcheson said. “The profile is the color standard, or the characterization of the device. What you want to do is use these profiles to communicate and to convert color from one device to another device. It’s a communication tool.”

ColorTune and QMS

In April, Agfa released ColorTune Pro 4.0, an ICC-based color management system.

The most important technical difference compared to the previous version of ColorTune is the new algorithm, which improves the quality of the scanner and output profiles. Dark colors and neutrals are cleaner and reproduce with greater accuracy.

The new version of Agfa’s color management software automatically compensates for differences in color ranges among input devices, monitors, printers, proofers and printing presses. The system can re-map the color space of a monitor and proofer to match the color gamut of a specific press.

For black generation editing, users can select between novice and advanced modes. In the novice mode, users select the black default and gray color removal/under color removal from a set of colored hexagons for automatic application. In advanced mode, users can edit the black curves to their specific needs.

The curve tool lets users edit individual RGB and CMYK channels. The gradation tool lets users adjust the luminance. They can lighten or darken tonal areas without affecting the other colors outside that area. The color correction tool gives the capability of doing small, precise color corrections.

The new version of ColorTune is also easier to use. Users can choose a wizard to guide them through the application step by step.

Available only on the Apple Macintosh platform, ColorTune Pro 4.0 is bundled with Sherpa digital proofing systems and AgfaScan scanners. The software is not sold separately. ColorTune is being used by The Wall Street Journal Europe as part of its Agfa-supplied prepress workflow system.

However, color management alone will not solve all the problems, Hutcheson cautioned: “The working environment must be very stable and the system has to be constantly calibrated and maintained. If you build a profile of a press and then you change inks or media, that profile needs to be changed and updated.”

Quality Management System is designed to give users the tools to control their digital proofing device to maintain a stable environment. QMS 1.0 was introduced in April, and Agfa will be demonstrating QMS 1.1 at Print ’01.

For proof-to-print, QMS verifies press color profiles, identifies press ink problems, verifies proofer color profiles, verifies tonal values and checks the proofer against press output.

The system also provides a history in the form of a time log, a problem/measurement report, a calibration and verification log, and a thorough quality report.

All of these components combine to create the Agfa digital proofing solution.

“The end result is a unique Agfa system that was built from the bottom up around customer needs,” said Stabler.