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Defining Addressability

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Picture Santa Claus covering the nation on Christmas Eve, but see every chimney as an ink-droplet address. See Rudolph rigged with aviator goggles and twin turbos.

In common terms, an address is a house or building number along a given street. Give a taxi driver an address, and he takes you to that location. The term is sometimes abstracted to include geographical locations, in degrees and minutes, that determine a longitude and latitude.

One nautical mile, for example, corresponds to a one-minute arc of the earth’s surface (latitude). At the equator, the earth turns 15° (longitude) every hour. Knowing this, and the vehicle speed, time traveled and the sun’s noontime height, a trained navigator can journey to any such described location on the planet.

For example, Las Vegas is at 36° 5 N latitude and 115° 10 ‘W longitude and Denver at 39° 45 N and 104° 52 W – a little math and hand-sketched vector reveals that a course of 76° northeast will take you from Las Vegas to Denver. Travel time depends upon speed.

It’s similar with a military-weapon system, except its GPS accuracy is down to 1/100ths of a minute.

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Addressing for signmaking

Vector-based cutting plotters also use numerical address systems to map their cutting path. Vector-based cutting plotters don’t cut curves; they cut a series of straight lines that appear as curves.

In recent years, cutting-plotter software engineers have quietly, but dramatically, improved their product, especially with “intelligence” additions to their vector-tracking systems. Graphtec America Inc.’s (Irvine, CA) new CE5000-60 series cutting plotters, for example, feature auto-registration-mark detection and dual-axis, four-point skew control. In a sense, it’s an automatic navigation system.

Digital printers place their ink drops on addressed locations determined by the RIP, which picks up (and modifies) the initial address from the image source, a scan, photo file or Illustrator® drawing. Every ink drop has an address, which is why print speed becomes important on extra-large images.

“Addressability” was concocted, I think, by a clever marketer, to better define his or her product’s features. The term speaks of a machine’s dot-placement accuracy and somewhat describes a print machine’s ability to locate, relocate, or near-locate, an ink-drop’s address, depending on the program application. Addressability has no scale; thus, it’s truly subject to various interpretations.

FujiFilm USA Sericol’s website, www.flatbedfacts.com, says dot (address) placement depends on a machine’s ability to handle certain variables: the distance between the printhead and media; the ink-drop size; the head-movement smoothness; print speed, and the application software and RIP.

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The machine’s base structure, especially as it ages, is equally important.

Fast-moving printheads, spraying ink droplets at high speeds, encounter certain physics problems, primarily, triggering the printhead as it passes over a given address. This may be akin to a bullet’s delayed-fire condition that affects a miss because the target has moved. However small,

that movement hurts image quality because all the ink drops end up in the wrong place. At high speed, a RIP must pre-fire the ink droplet, so that it lands in its proper location. Think about that equation.

The HP Scitex X2 printhead

Printheads are to digital print machines what fuel injectors are to racecars. Further, they deliver the ink droplets, and, although their technology borders on nanotechnology, they must be tough enough to withstand heat, vibration, damaging ink components and various cleaning solvents.

HP Scitex recently introduced its high-speed, piezo-electric X2 printheads that expose only silicon, glass and epoxy to the ink, making them highly resistant to corrosion.

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Developed exclusively by HP for HP Scitex, the X2 heads feature HP’s silicon-based, micro-electromechanical systems (MEMS) technology that enables, HP says, high-tolerance manufacturing that’s suitable for multiple-array applications. HP Scitex will fit the printhead into its future printers, made for printing signage, building and vehicle graphics.

Ask first

You can build the finest printer, or racecar, and fail when it comes to running it in the real world. The ultimate test is on the road.

I recently read, for example, that the 1974 Porsche 911, the one with the 2.7-liter engine, was a lemon. This is important to know if you’re a car collector — or, for that matter, a print-machine buyer — because it establishes that even the best manufacturers sometimes screw up. The ’74 Porsche fiasco came about because its Stuttgart factory engineers executed a series of ill-fated changes while attempting to meet the United States’ newly enacted, auto-emission and safety regulations.

Primarily, they modified the car’s engine-block metallurgy and cut the horsepower – the latter a cardinal sin in sports-car evolution. They also added heavy-duty bumpers and larger seats, making the ’74 911 heavier and slower than the preceding edition.

Once on the road, things got worse. The detuned 2.7 engine, an overbore of an earlier, 2.4l version, retained the former car’s cooling system and tended to overheat. Because the car’s engine block was magnesium and the heads aluminum, a heat-related expansion variation would, especially in hot climates, cause the cylinder studs to pull loose from the block — an event that could destroy the engine.

You’d think the Porsche engineers would’ve known better. You’d also think that current collectors would refrain from buying a ’74 model 911, at least one with the original engine type, but, get this, a Porsche chatroom “expert” recently recommended the ’74 to a first-time buyer.

Don’t be that buyer. Do your own research before purchasing a digital print machine. Talk to more than one person who owns a like model. N

SGIA Notes

• Nur America Inc.’s (Moonachie, NJ) 10.5-ft.-wide Expedio 3200 UV-cure printer, at its 1,300-sq. -ft./hr. speed, emphasized a primary theme — imaging speed — of printer manufacturers exhibiting at SGIA ’06, the September 26-29 Specialty Graphics Imaging Assn. (SGIA) tradeshow in Las Vegas. In addition to speed, tradeshow attention-getters were white ink; on-press color management (Nur introduced an on-board, automatic, color-management system); and soft-media, dye-sublimation printing. HP (Palo Alto, CA) with |2421| (New Windsor, NY), also makes an automatic color-management system, but it’s installed on the HP Designjet Z2100 and Z3100 photo printers.

• For printing soft graphics, Roland DGA Corporation (Irvine, CA), at its ever-popular booth, displayed its 74-in.-wide, Hi-Fi Express FP-740 dye-sub printer for flags, banners and textiles. Roland also honored PJ Brassard of LogosPrint.com (Albany, NY) as the grand prize winner for the first-ever Roland Wrap Vehicle Graphics contest. Additionally, |1949 (Wilmington, DE) showed its dual-gantry Artistri™ textile printer, and TexPress Inc. (San Diego), working with Japan Network Service Co., brought its TexPress DSS 1800II, a machine that’s in beta testing at this time.

• Océ USA (Chicago) received the DPI Vision Award for its Arizona 250 GT (see ST, October 2006, page 16). The award calls attention to a new, digital-imaging product development that’s most likely to have a profound and positive effect on the industry.

• SGIA ’06 was, possibly, the largest, digital-imaging show in the United States this year. Its show doors admitted more than 20,700 visitors to see 598 exhibitors. SGIA says 17.5% of its attendees were from outside the United States, with Canada, Mexico and Japan leading the 105 nations represented.

• At the show, SA International (Philadelphia) announced Donald Fegan as president and COO, and Mark Rundell, the previous president and CEO, was appointed chairman. Don was VP and business manager for Océ Display Graphics Systems, North America, not too long ago.

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