Copycat

"Digital imaging": the term sounds cool and cutting edge, right? Transforming traditional analog images into digital documents made up of millions of colored dots, or pixels, instantly brings to mind the hottest video technology or the latest digital cameras. But don't overlook scanners: they work perfectly fine when it comes to performing digital imaging. Although scanners predate the introduction of the Internet into most schools and libraries, and seem a little old hat, they're still the cheapest way to transform paper-based photos and artwork into Web-ready documents that can spice up your displays and presentations. That's why every public library and school library media center needs to own one.

When most of us think of a scanner, we visualize a flatbed model--a rectangular device with a hinged lid that hooks to a computer via a cable. If you lift up that hinged lid, you'll notice a pane of glass, similar to a copy machine's. Today's scanners, in fact, function every bit as well as many of the more pricey copy machines, and like copiers, scanners are able to duplicate a visual image and send it directly to a printer. And similar to fax machines, most scanners also have software that enables them to scan a document and place a phone call, as long as they're hooked up to a modem.

If you're strapped for cash, it's easy to find off-brand scanners on sale--check the big-name chain stores--selling for less than $100, or about half the price of name-brand scanners. These inexpensive scanners typically have resolutions of 300 dots per inch (dpi)--the bare-bones minimum required to print acceptable-quality images on paper. The more expensive (and more desirable) name-brand scanners cost $300 and up and feature resolutions ranging from 600 to 2,000 dpi, which result in images that are better in every way: sharper, more detailed, and larger.

The latest scanners are also available in other varieties besides the common flatbed model. Siemens and WizCom, for example, manufacture handheld scanners for $100 to $150 that are able to scan individual lines of text from books, periodicals, and other documents. These handheld scanners operate a bit like old-fashioned yellow highlight markers, but use AAA batteries and come equipped with Optical Character Recognition (OCR) software that turns lines of print into text that you can then download into your word processor.

For most people, a scanner is an arcane "black box" device: click a button, the machine's innards begin to whir, and an image appears mysteriously on the computer's monitor. But the operation of a scanner really isn't that hard to fathom. A flatbed scanner contains very few parts: a logic board that takes orders from the computer, a scanning unit with a light source and photosensitive silicon cells, guide rails, a belt, and a motor that slides the scanning unit beneath the image to be copied. To use a scanner, you simply place a photograph, drawing, or text document face down on the glass pane and push a button. The scanner's software tells the logic board where to move, and the motor and belt slide the scanning unit. A color scanner has three light sources--red, green, and blue--and sensors that measure the light reflected from the image being scanned. These bits of reflected light are then transformed into a digital image, or pixel pattern, and stored in a digital file. The most commonly used digital file formats are called TIFF (Tagged Image File Format) and JPEG (for Joint Photographic Experts Group). TIFF files are used when you plan to print the scanned images onto paper; JPEG files are used for images that you're planning to put on the Web. Your scanner's software will let you select the preferred format. Keep in mind, too, that for easy downloading, your Web photos should never be larger than 50 kilobytes.

Hewlett-Packard has been making high-quality scanners for a long time. Our test model, the Hewlett-Packard ScanJet 5300c (available online for $270 to $299), scans images at 1,200 dpi and comes with PrecisionScan software, a decent software package that includes Adobe PhotoDeluxe, a basic program for editing photographs. The H-P software package also includes a near-flawless Optical Character Recognition program that reads text and pictures.

That said, our test model experienced a couple of hiccups. When, for instance, I asked the Scanjet 5300c to copy a captioned illustration, I had to tinker with the software--selecting one setting for copying the text, another for scanning the picture. The software should have been able to do this automatically. But once made aware of the visual differences, the scanner performed perfectly. Later, when I tried scanning some larger book pages that included both text and photographs, the ScanJet 5300c initially had trouble getting the paragraph breaks correct. But aside from these few correctable glitches, I found the ScanJet 5300c to be an excellent piece of equipment--one that I'd recommend to any library.

Walter Minkel is technology editor of School Library Journal.