Scanners
Scanners are becoming more and more part of the home PC scene. If you're thinking about getting one, you should find some helpful information here, and if you already have one we'll cover some scanner basics that will hopefully fill in a few gaps for you too.
Once you have a scanner set up and you become confident using it, you'll be able to bring text and graphics into your documents, email photos to friends, and delve into the wonderful if not bewildering world of graphics. Information on scanners and how to use them can be very technical and just too much for the average person. Here, we are only covering the basics. If you want more detailed help, see our Links page.
The most common type of scanner for the desktop computer is called a flatbed scanner. It looks like a photocopier in that you place your document or photo on a glass plate and close the lid. The scanning head moves under the glass plate and the document stays still on top of the glass. These scanners can cope with documents of various sizes and also do well with small 3-d objects.
Individual flat bed models differ from one another in case design, size and quality of construction, connection type, scanning area, software and price. Invisible features that need to be considered when buying a scanner are resolution, bit-depth and speed. For average home use a 300 dpi scanner will do the job fine.
If you plan on printing out enlarged images, you may want to go up a level to a 400 or 600 dpi. Pictures that are to be printed on a laser or color printer should be scanned at under 300 dpi for best results. For viewing on screen, such as for a website, resolution needs to be even lower -between 70 and 100 dpi. Higher resolution slows down the loading of the images and computer monitors are only able to display a relatively low resolution anyway.
The higher the scanner's bit depth, the more accurately it can scan and the better quality the result will be. Most color scanners today are at least 24 bit. Be aware that your monitor may not have the capacity to display the bit-depth that your scanner operates on. A patchy image may be the fault of an older monitor, not the scanner.
Scanning speed (as with printing speed) which stated in the scanner's specifications, rarely matches our experience in the real world. Variables include the type of connection, the memory cache and the driver software used. When you scan at a higher resolution, performance is noticeably affected too.
Even though we've quickly run through the different characteristics of scanners, it's only fair to say that when all's said and done, a scanner is only a scanner - a piece of hardware. It's the software that comes bundles with the scanner that you will mostly have to deal with - that is what will determine it's functionality for you. I've had great scanners with poor software, and budget scanners with excellent software. I would choose the second option any day!
Good scanner software will allow for color calibration. One of the frustrations of using a desktop scanner is that a scanned image can look different on screen than it does when printed, and both can vary quite a bit from the original. If you are really particular about this, the solution to this problem is usually color calibration (or color matching) software. For most people using a desktop scanner, accurate color is not as important as fast, pleasing color.
Bundled software should include am image editor, a program that allows you to make changes to the image files produced by the scanner. An example of top-end image editors would be Adobe Photoshop or Corel Draw. Do not expect to get these as bundled software! You are more likely to get something like Photo Impact. Sometimes an OCR program will be included too. OCR stands for Optical Character Recognition. These applications specialize in taking a text image such as a scan of a typewritten letter, and converting it from a collection of pixels back into text that can be edited in a word processor. Many of the leading manufacturers bundle OmniPage Limited Edition, which is a cut-down entry level OCR program. This is a good introduction to OCR and may be all you require, but if you decide you'd like more advanced features you can upgrade at a reasonable price. Good OCR software makes life a lot easier if you are planning on scanning text documents regularly. It avoids the re-typing scene, but you do need a good clear image to scan from, not an old faded-out faxed copy!
You should also consider how difficult it will be to set up your scanner. The center you are buying from may include setting up for you, which could be a bonus if a new card has to be put into your computer. Not every computer can run every scanner. There are also various connections available - scanner cables plug into a variety of ports - your CPU must have one available, or may need one adding in.
When all's said and done, there is a lot of fun and practical use in a scanner - just be prepared to put some time into it!
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