Scanners Buying Guide

from Overstock.com

The world is going digital, and many of us need documents and images in digital form or they can't be used to their fullest potential. Others need some digital files or the like to archive important documents or images in digital format. Unless you are the creator, getting hard copy digitized can be a challenge, unless you have a scanner. Scanners are like copiers, except that the output is a data file instead of a piece of paper. Scanners come in a variety of models, suited to the many electronics needs of large corporations, small business or the consumer electronics user.

This scanners buying guide includes some basic information to help you wade through the options and help you pick what will best meet your needs.


What you need to know

Scanner buying tips

Several different types of scanners are in common use today. The type best suited to your needs depends on your planned use:

  • Business card: Very small scanners designed for (you guessed it) business cards; a quick and easy way to keep your 'people' files up to date.
  • Document: Also called sheet-fed scanners, these look more like a printer; the pages roll past the scanner head, so you can scan many pages easily. You can only scan loose sheets. Some models are specifically designed to read text documents.
  • Drum: Designed for professionals, this large format color scanner rotates the document on a drum while a laser bounces a light off the document into a photo multiplier tube (PMT). This ultimate computer scanner produces a superb image. Unfortunately, prices start in the low five figures.
  • Film: Occasionally called a picture scanner, these are specialized units designed to scan film negatives, transparencies and similar non-paper items.
  • Flatbed: Probably the most common scanner, since most people rarely need to scan more than a few pages at a time. Works much like a copier: place the page on the glass, press the button and don't look directly at the bright light. A good flatbed scanner has a removable lid, so you can place odd-sized books, etc., on the bed; also better for scanning small items like photos or news clips.
  • Handheld: Many look like a large pen, some large enough to scan a full page of text (eight inches wide) on one sweep. Great for work in libraries or archives (with the librarian's permission--light can be very damaging to old documents) or when on the go. Battery powered; this digital scanner recharges via USB; as light as a couple of ounces.
  • Portable: A very basic computer scanner model, small enough to take almost anywhere; works well with laptops. Many are powered via their USB connection; sheet fed, as light as one pound.

Smaller or less expensive model desktop scanners will have fewer features and probably lower resolution, but within its designed use it is more than adequate. If you need to scan big pieces, a big flatbed scanner is the way to go. If you spend a lot of time out of the office, you may need a portable scanner or handheld scanner. Most any scanner will digitize images, so buy a film scanner only if you think you'll be scanning enough non-paper images to get your money's worth.

Scanner components

A few of the principle items:

Connection: Older scanners use a parallel port, a really wide connection that screws into the back of the computer. Most new model scanners use a universal serial bus (USB) connector. Some even draw power via USB, eliminating one more cable from under your desk. Large format scanners have a FireWire (IEEE 1394) cable, which allows a higher data transfer rate--not a necessity for most home or small business operations.

Document feeder: Available in higher-end flatbed scanners as well as sheet-fed scanners, it moves pages through the scan automatically.

Sensor: The 'eye' or camera of the scanner, two types are most common in today's scanners:

  • Charge-coupled device (CCD): The same device used in digital cameras. CCDs use a mirror to bounce bright light off the page, exciting pixels and capturing an image. CCD scanners produce clearer, higher resolution images.
  • Contact image sensor (CIS): Placed close to or in contact with the page, bounces light directly off the page through a lens to create the image. CIS scanners can be more compact, more durable and use less power.

Software:

  • Driver: The software that runs all computer-related devices; it usually comes on an accompanying CD. When a new device is hooked up, drop the CD in the computer's drive and installation is nearly automatic. When scanners have problems, sometimes the solution is as simple as uninstalling and reinstalling the driver.
  • Twain: A software standard created in 1992 to assure that every computer, digital camera, digital scanner and similar device could communicate. It processes scanned images into computer files. (The name was taken from a poem by Rudyard Kipling, "east is east and west is west and never the twain shall meet." Fond as they are of fancy acronyms, software engineers didn't have one in mind when they chose this name, so it now stands--unofficially--for "Technology Without An Interesting Name.")
  • Optical Character Recognition (OCR): An OCR software package is standard on most scanners; it allows the scanner to "read" text by matching the printed characters to letters, numbers and punctuation marks and transferring them to text files.

Scanner terminology

Bit depth or Color depth: 'Bits' are individual data points (1 byte = 8 bits). Higher depth (or should that be 'deeper depth'?) means greater contrast or differentiation. For text, a 24-bit scanner is good enough. For negatives, slides and transparencies, 30 or deeper is recommended. For photos or color graphics, 48-bit is the way to go.

Imaging can comprise two factors:

  • Resolution: Measured in pixels-per-inch (ppi), sometimes called dots-per-inch (dpi), this is the number of picture elements that comprise an image. Resolution is dependent on the CCD or CIS hardware. Scanning text at 300 ppi is usually sufficient. Proper photo scanner resolution depends on how much you might enlarge or how detailed the final image must be; 600 ppi is enough if the photo file won't be enlarged. Slides or negatives should be scanned at 1,200 ppi or above.
  • Interpolation: Scanners that advertise super high resolution, 4800x4800ppi or above, use software to add pixels between those scanned by the CCD or CIS. The scanner averages the color of the surrounding pixels and makes a 'best guess' as to what color a pixel in between would be.

Scanner care

Unlike many other electronics, desktop scanners have moving parts that can wear out. Manufacturers' warranties vary--90 days to one year is typical--and many scanners live far beyond their warranty.

Dust is probably a scanner's biggest threat, so a scanner should occasionally be blown clean with canned air (never your humid breath). Also, cover scanners with a cloth or plastic sheet when it will not be in use for a while, such as overnight, and your scanner will stay cleaner and healthier longer.

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Common scanner questions

How do I fit all these machines on my desk?

In a word, multi-tasking: If you are short of desk space, or you just don't want to clutter the deck with electronic paraphernalia, consider what's variously called an all-in-one printer or multifunction fax machine (no, scanners never get top billing). These multi-taskers combine a scanner with a fax, a printer and a copier. It is a great space saver and, generally, costs less than buying all four consumer electronics separately.

Of course, if you want a room full of electronics, Overstock.com will happily sell them to you and save you a boat load of money on the shipping!

Can I still get a black & white scanner?

Yes, but it will probably be a big one. Among consumer electronics, a black & white scanner becomes harder to find every year. A color flatbed scanner is so widely available and so affordable, it seems that only multi-user office size all-in-one printers come as black & white or color scanners.

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Ideas from Overstock.com

Scanners generally aren't any good unless they're hooked into computers to process and store the data. If your computer is more than a few years old, it is definitely time to look at upgrades or a new system. Fortunately, at Overstock.com, your new system probably won't cost much more than the one you're replacing.

If your desk does seem crowded, maybe you simply need a bigger desk. If not, well, you're saving so much money buying new electronics, it seems a shame to put those shiny new machines on a scratched up writing table. Either way, drop by the Overstock.com furniture store and be amazed at the wonderful office furniture you can get and prices that are so low, they should be illegal.

And, while on the subject of the office--you've spent a lot of time with CCDs and ppis this week. The weekend is coming; grab your GPS-equipped PDA; turn off your LCD or DLP TV, your MP3 or CD player player, your DVD or VHS and your VG console; then tell your CEO you're hitting the road to see the USA in your new SUV. (Don't forget your cell phone and camcorder!)

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