The Contract Proof - 2000
Is a digital proofer on your shopping list? Which digital proofing devices will you buy this year? What will be the improved range of spot colors accurately produced by these devices? Who's talking stochastic? Find out—today.
BY MARIE RANOIA ALONSO
Happy new year. Need a new digital proofer? What an interesting time to shop for proofing expertise. (Sorry. No after-Christmas clearance on these items!)
Expanding color gamuts, open front ends, new media selections, pigment-based inks, digital halftone and ink-jet devices, multi-setting proofers, spot color surprises—it seems every flavor of digital proofer is pushing to better mimic press conditions, deliver stable, accurate color and provide commercial printers with the best tool for making the customer happy: the contract proof.
Easier said than done? Maybe not. As the long-awaited year 2000 takes form, with a competitive DRUPA 2000 pushing technologies to improve for global review in May, contract proofers, sporting better color management, expanded spot colors and flexible multisetting capabilities, are prepared to push the contract digital proof to the next level.
Kodak Polychrome Graphics reports that the Kodak Approval XP4 halftone digital color proofing system with Open Front End (OFE) will provide users with the ability to proof confidently from a wide selection of digital front ends, including Scitex Brisque, Creo Prinergy, Harlequin, Barco, Rampage and others.
In early 2000, Kodak Polychrome Graphics plans to further enhance the already powerful Approval proofing system by adding the capability to proof spot colors—including metallics. A halftone digital proof will be able to accurately portray fifth and sixth-plus colors—plus gold and silver. Additionally, new Kodak Type 2 Color Proofing Media will allow other proofing devices to produce highly accurate halftone proofs. Type 2 Media will be compatible with such devices as the Creo Spectrum, and proofsetters from Scitex and Optronics.
Kodak Polychrome Graphics reports the media features outstanding writing speed with the predictable and accurate color set that has made Kodak Approval the "digital proof of choice."
Polaroid Graphics Imaging reports it will continue to do its part in the migration to an all-digital workflow by maintaining truly digital, high-quality proofing systems.
"In the new millennium, our proofing technologies will enable the commercial printer to have a distinct advantage in this increasingly competitive, dynamic digital age—an age that demands better color," reports Betty LaBaugh, director of worldwide public relations at Polaroid Graphics Imaging.
"The need for better color means providing high-quality, consistent and achievable color from the proof to the resulting press sheet, without extensive intervention."
Polaroid believes the best way to achieve this is in a proof that replicates the printing process—fixed density pigmented inks imaged on actual printing stocks.
"Industry trends seem to bear out that we built our proofing systems on the right theory—mimicking press conditions," LaBaugh asserts. "Contract proofing is now moving toward fixed-density, pigment-based inks. Pigmented inks are used on press and they are more stable over time vs. dye-based proofs."
But having stable color is one thing. Having the right color to begin with is another. The big question facing commercial printers intent on consistent proofing is: Does the right color mean a universal color standard?
LaBaugh takes a shot: "Some industry gurus are working toward a universal color standard. There is even a prediction that the universal standard will be based on a cleaner, more saturated color set—Hexachrome could be seen to fit the bill for those criteria," she reports. "Whether the standard is universal or based on an existing industry standard, we are committed to providing a range of industry-standard color sets—SWOP, GRACoL, Hexachrome, Eurocolours, also Opaque White and Pantone specialty colors including metallics."
Polaroid's theory on color management is that "when you start out with the right color, color management becomes a whole lot easier." Therefore, logically, a trend to watch throughout 2000 in streamlining digital workflow is the integration of stochastic screening.
"A well-known printing company tested stochastic screening in a CTP workflow. The results reportedly claim that stochastic is easier to run than conventional screening—no moiré and higher quality reproduction of more detail in a wider latitude with a greater dynamic range," LaBaugh reports. "A big benefit is consistency. Stochastic screening was once thought of as difficult to reproduce, but now with the fine dot reproduction and minimal gain capabilities of CTP systems, stochastic has the potential to flourish by providing a defining competitive edge—stochastically screened digital proofs need not be a missing link in workflow."
Watch the proofing directions of Agfa, Creo/Heidelberg, Fujifilm, Kodak Polychrome Graphics, Polaroid, Optronics, Scitex, Screen (USA) and other top manufacturers. Multi-setters will be in vogue in 2000, offering the flexibility of plates or proofs to a market demanding both—fast.
2000 Is the Year For Drop-on-demand
By Deborah Hutcheson, senior product marketing manager, proofing, Agfa Corp.
In seeking a digital proofing strategy that would take us into the 21st century, Agfa carefully examined every available technology. The clear winner from all angles was ink jet—not just because of what it can do today, but more importantly for its future potential. Amazing as its progress has been over the last five years, ink-jet technology is still in its infancy, and most people will see it advance beyond their imagination in the next few years.
Here is an overview of why Agfa chose the ink-jet path, the advantages it offers and what proofing users can expect from this technology.
- Ink-jet proofing offers seven major advantages over other systems.
- Low capital equipment investment avoids costly commitment in an age when devices become obsolete before they are paid for.
- Low cost per proof (eight-up contract proof under $10) allows more proofs for less money and permits internal proofs that were never before affordable.
- High productivity (720x720 dpi eight-up contract proof in less than 18 minutes) avoids proofing bottlenecks, shortens deadlines and helps reduce proof costs.
- Multi-density inks yield expanded color gamut and—through color management—the potential to match HiFi ink sets as easily as standard ones. The proofer can even be used for short-run, high-gamut print jobs.
- Ink jet is extremely consistent compared to dye-sublimation halftone proofing.
- The technology is evolving so rapidly that major quality and productivity improvements arrive each year. Thanks to the low cost of equipment, users can afford to keep up with these advances.
- Resolution enhancements and screening technologies are beginning to allow accurate screened proofs at a fraction of the cost of other halftone digital proofers.
There are two types of ink jet—continuous flow and drop-on-demand. Continuous flow ink-jet systems deliver superb quality, virtually continuous-tone images. Rapid bursts of "micro-drops" form each single droplet, whose densities are varied by varying the number of micro-drops from which each is made. Only a small number of density levels are possible, so the system is not truly "continuous tone." But by screening with these variable-density droplets, ultra-smooth prints are possible at relatively coarse device resolutions.
Because continuous-flow printers are drum-based, they are expensive to build, and because a continuous flow of ink is required even when printing white areas (the unused ink is deflected into a drain), ink is a major cost.
Drop-on-demand ink-jet technology produces ink droplets only when needed, so no ink is wasted, and it is by far the faster of the two methods. Instead of varying drop size, dithering (variable droplet spacing) is used to achieve tonal variations.
Drop-on-demand ink-jet technology comes in two flavors—thermal and piezo-electric. Thermal ink jet actually heats the ink to push it from the nozzle. Piezo-electric technology applies pressure to squeeze the ink out of the nozzle.
While thermal is faster, the speed comes at a price. Heating the ink causes some colors to shift and creates a larger, less consistent droplet. Piezo ink flows better, with smaller droplets that make sharper prints. Piezo ink colors are also purer, and piezo printheads do not need to be replaced at regular intervals, the way thermal printheads do, which translates into greater stability.
And now—true halftoning.
One Halftone Analysis
The main argument against ink-jet proofing was always the lack of halftone dots, but this limitation is passing. As ink-jet resolutions approach those of an imagesetter, halftone-accurate ink-jet proofs up to 175 lines per inch are now feasible.
The main reason for halftone proofing is to predict moiré. At 720x1,440, the current AgfaJet Sherpa 43 can already generate 70- to 100-lpi screen-angle rosettes and, with future enhancements, the Sherpa will simulate 150- or 175-lpi screens. If the same RIP is used, the halftone dots will be the same shape, ruling and angle as those on the press sheet—not just an approximation.
Ironically, Agfa's initial research showed that a large majority of potential digital proofing users couldn't care less about halftone dots, so long as they got accurate color and consistency. But if we can give them dots and color accuracy and speed and economy and consistency, we figure no one's going to complain.
Why six colors? The most important advancement in drop-on-demand ink jet has been the addition of continuous-tone capabilities through more than four inks, i.e., multiple densities of the basic four colors. For example, the AgfaJet Sherpa 43 adds a light magenta and a light cyan to the CMYK process. This multi-density approach solves the problem of graininess.
To achieve a 50-percent tint by four-color dithering, half of the paper area is covered with droplets of full-strength ink. In the six-color process the two magentas (light and dark) are blended to create the 50-percent tint. The presence of the lighter ink around each darker droplet reduces the apparent contrast between white paper and the darker ink, making the droplet pattern much less visible.
Agfa's digital proofing strategy adopted drop-on-demand piezo ink jet because the technology was stable, color-accurate, affordable and rapidly evolving. The fact that we will soon offer halftone screening is an added bonus that few of us expected five years ago.
Just imagine what the next five years will bring.