Classic Computer Magazine Archive COMPUTE! ISSUE 130 / JUNE 1991 / PAGE 36

Canon BJ-330. (bubble jet printer) (evaluation)
by Denny Atkin

There's an entire cottage industry devoted to creating huge, heavy, sound-dampening enclosures for high-speed wide-carriage printers. Most of these heavy, bulky printers can be heard in the office on the other end of the hall and shake the entire desk, if not the room.

Now there's a light, fast, and quiet alternative. Canon's BJ-330 uses bubble-jet technology to provide fast, crisp, clean wide-carriage output without the need for earplugs, enclosures, or a reinforced desktop. In fact, the only sounds you'll hear from the Canon are the printhead moving back and forth and the paper being fed through the printer.

Instead of striking a fabric ribbon with a set of pins or burning toner onto a page with a laser, the Canon printer fires ink droplets at the paper from thin nozzles. The term bubble jet comes from the process used to spray the ink. When ink in the thin nozzles of the printhead is heated rapidly, tiny bubbles are produced. As the bubbles expand, ink is ejected from the nozzle.

Early ink-jet printers, such as the original Hewlett-Packard DeskJet, used a water-soluble ink that would smear if any liquid touched the page. The Canon's ink is waterproof (as is HP's new DeskJet ink) and prints on standard fanfold, letterhead, or copier paper. You don't have to use the hard-to-find and expensive ink-jet paper required by earlier printers.

While the Canon uses an ink-jet technology similar to that of the HP DeskJet, which emulated an HP laser printer, the Canon emulates a dot-matrix printer (either the Epson LQ-1050 or IBM ProPrinter XL24). Because of this, the Canon's graphics output is only a little better than the dot-matrix output of printers it emulates. HP's similar offering, on the other hand, provides graphics output nearly as good as that of its laser counterparts. The DeskJet's fonts are also more laserlike than the BJ-330's. The newest HP ink jet, the DeskJet 500 includs scalable Compugraphic laser-printer-style fonts, which can be printed at just about any point size. The Canon's dot-matrix-style fonts are only available in fixed point sizes. Font cards that ad new typeface styles and sizes are available for the Canon, however.

While it doesn't quite match the DeskJet in output quality, the BJ-330 eclipses it in flexibility. The HP printer (and most lasers) will accept only single-sheet letter- and legal-size paper; however, the BJ-330 accepts paper ranging from 3 1/2 to 17 inches in width. The printer handles fanfold and single-sheet paper. A must-have option is the dual-bin sheet feeder. With both bins attached, the printer will automatically feed both plain paper and letterhead, switchable with the press of a front-panel button. Envelopes can be loaded individually or installed in a sheet-feeder bin.

There are three selectable paper paths: top, rear, and front. You don't have to remove the fanfold or sheetfed paper to run a special form or envelope through the printer; just place it in the front slot.

You set rarely changed options, such as emulation and interface selections, using a set of DIP switches on the back of the printer. Fonts, paper bin selection, print quality, and other options can be easily modified using a number of easily accessible front-panel switches.

This printer is a great example of doing it right--after a month of heavy use, I have no complaints. If you need a fast, quiet printer with flexible paper handling and don't need to print multipart forms, fire up a Canon BJ-330.

Descenders, Pixels, and Jaggies

Since the early days of computing, certain nightmarish apparitions have haunted computer printouts. One is the descender. Early computer printers were unable to hang the lower part of a lowercase g, j, p, q, or y. Instead, the entire lowercase letter was elevated to fit within the seven or eight pins used to print the bodies and ascenders of other letters. This made a computer printout look terrible and could even be confusing because there was little or no difference between an upper-and a lowercase p. Fortunately, this problem was solved to some extent by the appearance of 9-pin printers and eliminated entirely with the advent of the 24-pin printer.

Graphics resolution has also long been a problem. To begin with, printers often took the graphic directly from the computer screen, transferring it pixel by bixel to the page in the form of ink dots. With the 72-dots-per-inch resolution found on most computer screens, that made for a very blocky drawing. Even when paint programs were supplanted by draw programs, which could send higher-resolution graphics to the printer, the problem caused by lower printer resolution remained.

The term jaggies refers to the saw-blade (or stairstep) appearance of slanted or curved lines. Jaggies occur because you are trying to print a line that is not perfectly straight and perfectly horizontal or perfectly vertical--the only kind of line a raster device can create. All printers except daisy wheel printers and plotters are actually raster devices, which must approximate curves by carefully placing assemblages of straight lines. You don't notice the jaggies so much with a laser printer (and even less with a typesetter) because the reaster lines are much finer than the raster lines of a dot-matrix printer or your monitor.

As laser printers achieve ever higher resolutions and employ tricks like the Hewlett-Packard Laser Jet III's variably sized dots, jaggies will become tamer creatures that may one day disappear from computer printing.