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Ed-Tech Trends (untitled)

Once reserved mainly for schools' art departments and multimedia laboratories, scanners have slowly found their way into more administrative offices, libraries and classrooms. Educators in all disciplines use these devices to input hardcopy drawings, slides, photos, etc., into their computer. The main reasons for the growing popularity of scanners in mainstream environments: falling prices and expanding features. While early desktop scanners cost thousands of dollars and offered only poor-quality grayscale input, today's units capture photo-realistic colors at high resolutions and sell for as little as $500. Minimal Training Required Scanners have also become easier to use. As a result, one d'es not need to be a graphic artist or desktop publisher to exploit this technology. With minimal training, teachers can add pictures to lessons or presentations, students can produce visually rich reports, and library staff can preserve valuable images in electronic form, among other things. These products fall into several main categories: flatbed, sheetfed, hand-held, transparency and drum. Hand-held scanners cost as little as $100, but require a steady hand to operate and typically deliver low resolutions; they work best with small originals. With sheetfed scanners, originals are fed one at a time into a motor-driven slot; one drawback is that these units can't handle 3D objects. This article focuses on flatbed and transparency scanners&emdash;by far the most useful for multimedia. Drum scanners are also examined, but their steep prices place them out of reach for most individuals. In the past year, low-cost color desktop scanners have flooded the market, causing grayscale models to virtually disappear. Although many units look alike, there can be important differences. As with printers, dpi (dots per inch) is the critical spec for a scanner. Higher numbers mean more detailed images. Though 300, 600 and 1200 are all standards, 1200 dpi d'esn't cost that much more and its quality is vastly superior. Be sure to check the results of interpolated dpi figures. In interpolation, software looks at two adjacent pixels in a scanned image and averages them to create an intermediate value. Some other guideposts: 8-bit color depth is standard; 24-bit depth usually means three passes, scanning for red, green and then blue. Dynamic range refers to the number of tones, from the purest whites to the deepest blacks, that hold detail after scanning; it is measured from no density (0) to maximum density (4.0). Finally, most scanners are bundled with image-editing software, which lets users alter color, hue, orientation, sharpness, shadow and other qualities to achieve the finished image they desire. Flatbed Units Gain Ground Flatbed units have gained the most ground in recent months. Resembling a small photocopier, they utilize a moving bar of light that passes under the image being scanned. Prices go from $400 to $6,000, with $2,500 buying a unit capable of 1200 dpi. Surprisingly, photographic scanning seldom requires a resolution greater than 300 dpi. For line art, however, a higher dpi helps eliminate imperfect edges, or "jaggies." From Sharp Electronics comes the JX-330, a multi-purpose 600 dpi flatbed scanner for under $1,500. This scanner utilizes the firm's patented process of strobing three colored fluorescent bulbs in a single-pass scan. Included in a single box are the full version of Adobe PhotoShop and Sharp's ScanJX utility, which allows precise control of most scanner functions directly from Macintosh or Windows screens. For more sophisticated applications, the JX-610 offers 36-bit color, 12-bit downloadable gamma tables and 1200 dpi resolution. Built-in functions control lightness, edge emphasis and gamma correction. A large 12" x 17" scan bed handles 35mm slides, film, comps and even X-rays. A standard SSCL language and dual GPIB and SCSI-2 interfaces provide the broadest compatibility with existing computer platforms as well as present and future software. Hewlett-Packard's highest image quality scanner to date, the ScanJet 3c offers double the speed performance of the ScanJet IIcx, which it replaces. The 600-dpi optical resolution and 30-bit color internal capabilities provide increased control in maintaining original image quality when scanning and enlarging images. Its software bundle comprises Corel Photo-Paint 5.0 (Windows) or Adobe PhotoShop LE (Macintosh) image-editing software as well as text-recognition software. In addition, the ScanJet 3c includes a new copy utility that, when used with a printer, creates color or black-and-white copies with one mouse click. The unit comes with a limited one-year warranty that includes HP Express Exchange Service (U.S. only), which provides next-day delivery of replacement scanners. Free technical support is available via prerecorded Audio Tips and HP FIRST, a fax-back service. A New "High-Bit" Breed Both the ScanJet 3c and Sharp's JX-610 are part of a new breed of "high-bit" scanners, which capture more than 8 bits of data per pixel. Because some information is lost during analog to digital conversion, these extra bits provide more accurate color shading and saturation and greater image detail. Epson offers low-cost, high-resolution color scanning solutions for Macintosh, Windows and DOS platforms. Targeted at professional graphics users of all levels, the ES-1200C provides 30-bit internal, 24-bit external, color scanning with resolution of up to 4800 dpi (2400 dpi for PCs). Both SCSI and bi-directional parallel interfaces are standard, allowing for connections to two computers at once. The scanner has a true optical resolution of 600 dpi; higher or lower resolutions are achieved through interpolation. Plus, Epson's exclusive TruePass technology provides built-in monitor and printer calibration. One may capture full-color, grayscale or black-and-white images with single- or three-pass scanning. Similarly, PixelCraft's Pro Imager 4000 offers the output quality, productivity tools and control often associated only with high-end commercial prepress systems. Its fluorescent lamps generate no heat, eliminating the need for ventilation or a fan. For Macintosh enthusiasts, adding sharp color graphics and images to documents is simple and fast with the Apple Color OneScanner. Users can scan files with the resolution of their choice: 75, 150, 300, 600 or 1200 dpi. Plus, the Color OneScanner supports ColorSync, Apple's unique color matching software, assuring accurate colors and tones from scanned input to display to printed output. Other highlights are one-button, fast-pass scanning, Balloon Help for interactive learning and powerful yet easy-to-use rotation, selection and scaling tools. The unit ships with Light Source's Ofoto scanning software, which features a virtual imaging system to handle large image files by expanding system memory with hard disk space. Educators will also want to consider the range of media types and sizes a scanner handles. Agfa's StudioScan II scans both reflective and transmissive originals in one pass. And the FX-RS308Ci from Panasonic provides a 8.5" x 14" scanning area and detachable cover to accommodate large or bulky originals such as books or mounted graphics. Other manufacturers of flatbed scanners include Microtek Lab and UMAX Technologies, both of which recently reduced prices by as much as 30%. "This will be a watershed year for the scanning industry, with color desktop scanners becoming a mainstream consumer product by year end," predicts Woody Hale, Microtek's vice president of marketing. For Specialized Applications While flatbed scanners suffice for most educational applications, some demand the ultra-high resolutions of drum scanners. With price tags to match ($20,000 to start), these target professional publishing. However, institutions creating commercial multimedia might want to invest in one. ScanView offers a broad line of drum scanners, including the ScanMate 3000, a single-pass unit with three photomultiplier tubes (PMTs). It boasts 3000 dpi resolution, an autofocus motor for razor-sharp scans and an output density of up to 3.6 Howtek's Scanmaster 4500, meanwhile, achieves 4000 dpi as well as 12 bits per color or 4,096 levels of gray. The firm's optional Aurora software precisely controls the color of scanned images; its pre-defined setups adjust to a range of negative films with a minimum of operator intervention. On a different note, transparency scanners, also called film or slide scanners, handle 35mm slides, transparencies and photographic prints. Typically, they offer finer resolution and can be a useful adjunct, for those with libraries of slides for example. Unlike with drum scanners, preparing a film for a transparency scanner requires little time and no special skills. Some models also support automatic loading and batch or gang scanning of framed transparencies. Polaroid's SprintScan 35, for example, digitizes 35mm slides at maximum resolution in about 30 seconds&emdash;five to 15 times faster than other leading desktop slide scanners. It scans in a single pass and outputs at resolutions of up to 2700 dpi, capturing 10 bits per color at 3.0 density range. Utilizing proprietary electronics and sensor technology, the unit automatically corrects color and sharpens images during scanning, reducing the need for post-processing. SprintScan 35 accepts any color or B/W 35mm transmissive media, including positive and negative, mounted or unmounted transparencies and film strips. Another 35mm film scanner, Nikon's LS-10 Coolscan incorporates the firm's patented LED illumination technology to achieve a full spectrum output with low power consumption, virtually no heat dissipation or noise, and added durability. A film strip holder lets one scan film strips up to six pictures in length, without having to cut the strip. External and internal versions of the Coolscan are available; the latter requires a half-height 5.25" disk drive bay and mounting kit because it g'es inside the computer. Finally, the RFS 2035 Plus Film Scanner from Kodak sports a custom-designed lens for high-quality 2K x 3K scans. An advanced area array sensor translates into fast scans&emdash;about 11 seconds for a 4.6MB (1000 dpi) image. As with flatbeds, high-end transparency scanners are available, such as Crosfield's CELSIS 360, which scans at a maximum resolution of 6583 dpi and allows enlargement up to 2000 percent. Other Innovative Approaches For a cost-efficient approach to scanning, a few firms have introduced products that allow standard fax machines to scan images into a PC. Zoom Telephonics, for example, now includes a Hotscan feature on some of its fax modems. Simply plug the fax machine into the fax modem's second or "local" phone jack. When a certain number is dialed, Hotscan switches the fax machine to its own circuitry and signals the software as if a call were coming in. With such a solution, even young children can get in on the action, using widely available fax machines to scan diagrams, drawings and more. Given the proliferation of multimedia hardware and software, scanners are likely to play a growing role in education, spurring further creativity and productivity among teachers and students alike.

This article originally appeared in the 06/01/1995 issue of THE Journal.

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