What type of output are you trying for? This sets the resolution you need to scan at to get the best image. Most low price scanners are 300 x 300 or 300 x 600 dpi (dots per inch, ďactualĒ not ďinterpolatedĒ). The next price bracket is for 600 x 600 or 600 x 1200 dpi.
All measurements below assume you are not enlarging the image. Enlarging the image to twice its original size requires scanning at twice the resolution you need in the final image. For example: you have a 1 inch square line art logo and want a final 2 inch square image to print well on your 600 dpi laser printer. Your scanner must be able to scan at 1200 dpi to give you the best output. Scanner software can guess at how higher resolution should look. This is called ďinterpolationĒ and is not as good as being able to really scan at the higher resolution.
What size pages are you scanning? While most scanners scan up to letter size pages, some do legal or even tabloid (11x17).
Are you scanning single pages or books? Single sheet scanners take up little space but you must photocopy a book or magazine to make sheets to scan. These days flat bed (desktop) scanners are in the same price range as sheet fed scanners so, unless space is a major factor, you probably want a flat bed scanner for the convenience. Some scanners have an adjustable top which lifts to accommodate thick books.
You can also get transparency adapters for scanning slides and adapters for auto-feeding pages for OCR.
Durability vs. price. Hewlett Packard makes bomb-proof hardware (my 8 year old HP scanjet plus still works fine) but they are almost twice the price of similarly capable scanners. The interface (the software you use to work the scanner) for their newer scanners will not let you pick your resolution directly: you must fool it by telling it that you are printing to an imagesetter or other high resolution device in order to scan at higher resolution (Check www.hp.com for a new driver which may fix this). Umax is very good value but ... may you never have to deal with their tech support folks. 6 years ago I had a problem and Iíve been mad at them ever since. Two months ago I went scanner shopping. The Umax Astra 1200s had all the features I wanted at 1/2 the price of others. It was very well reviewed. I decided to give them another try. The power supply broke after 6 weeks. Other Brands with good reputations: Microtek, Epson, Visioneer, Agfa ... new ones come on the market all the time. Only in retrospect can you say for sure that the company will be around long enough to support the warranty.
Ease of use ó New scanners should be TWAIN compliant.
Does the scanner come with software for OCR (Optical Character Recognition) for making editable text files? I think the best package is Omnipage Pro but many of the others are very good.
Does it come with software for editing photographs? Adobe Photoshop is by far the best package (donít confuse this with Adobe PhotoDeluxe which is painfully limited or Photoshop LE which is also limited). Corel Photopaint isnít quite as easy as PhotoShop but it isnít bad. Many of the scanners come with small packages which will do just enough for you to get it to print well on an inkjet or laser printer (but not for high resolution printing) and thatís all many people need.
Quality of image: For printing to an inkjet most color scanners will do. PC Magazine does a review of scanners at least once a year with pictures of the original vs. the scan. Of course, the models available change very fast so it isnít as helpful as you might wish. Their web site, www.zd.net/products/scanneruser, has lots of reviews and I find them generally trustworthy.
Ink: The many colors are made by over printing dots of Cyan, Magenta and Yellow. Most modern printers add Black (the K in CMYK) for text printing and because CMY together is a bit greenish rather than true black. Some printers are refillable by color rather than having to toss the whole thing when you run out of one color. How much does ink cost for how many prints? Do you need waterproof ? Canon seems to have the only really water resistant inkjet ink (Tektronix wax printers are really waterproof but more expensive).
Color calibration is an issue and most of the printers in the low end pricing arenít calibrated to any standard.
Resolution: you canít just go by the numbers. Dot size is a major factor and this is influenced by paper. You want to compare output on the same type of paper rather than looking at samples set up for best output.
Paper path: I prefer a straight paper path so I can feed cloth and envelopes through it. HP printers donít have a straight path but most of the rest do.
Paper size: letter and legal size work fine for most people. Iím interested in the 5-page fanfold banner size and tabloid size for cloth stuff.
Do you need networking capability beyond parallel printer sharing? HP and Epson seem to lead in this area. Look for built in Ethernet (or Appletalk if Mac).
How do you want it connected: Parallel or SCSI. SCSI is faster but you have to open your computer and install a card if you donít already have a SCSI port (Macs do, most others donít). You may have to pay extra for the card and you may not have a slot for it. Parallel is easier but if you have other devices like a Zip drive or a printer you might have interference problems (not usually, but be sure to look for this during the ďreturn within x daysĒ).
Give us a call at 206-523-0872 if you have further questions.
copyright 1998 Karen Seymour
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