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Defining Addressability

(January 2007) posted on Tue Jan 09, 2007

It’s about getting there and back again.


By Darek Johnson

click an image below to view slideshow

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.

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.


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