Which new scanner should I choose to buy ?
by Tom Cumming
Things to consider when choosing a new scanner:
1) Interface. This is the way the scanner connects to the computer. There are several different connection types to chose from:
a) Parallel (printer) port: The "traditional" way of connecting a scanner to your PC is via the parallel or printer port. The reason for this is that virtually every PC, besides some of the latest legacy-free designs, and a lot of recent Applemacs, has a parallel port. By buying a parallel port scanner, you can be pretty sure that you will have the correct port to connect it to. However, there are a few drawbacks. Firstly, the printer port is often used, not surprisingly, for a printer! Have a look round the back of your computer and see if the 25-pin parallel port has your printer connected to it. If it does, this may present a problem. Most parallel port scanners do have a "pass-through" plug on the back, so that you can plug your printer into the back of the scanner, and then the scanner into the computer, but these are notoriously troublesome. Some times they work, some times they just don't, and there is not an awful lot you can do about it. The only real way round this is to buy a second parallel port card for your PC, to give yourself a second printer port. They cost £10-£20 and require a free ISA expansion slot. Parallel port scanners are also rather slow.
b) External SCSI port: SCSI (Small Computer Systems Interface) is an "alternative" way of connecting many devices to your PC, both internally and externally, which is faster than the standard PC parallel and serial ports. If your printer port is occupied by a printer, and you do not want to use a "pass-through", or you want something faster, you could try a SCSI scanner. The main drawback of SCSI is that most PCs do not come fitted with SCSI connectors as standard, though a lot of older Applemacs used to. This means that unless you have already added a SCSI card to your system for something else, you may have to buy a SCSI card to use one of these scanners, adding to the cost. However, some SCSI scanners come with a basic cheapo SCSI card in the box to get you started, so ask the manufacturers. If you are not sure whether you have a SCSI card or not, you almost certainly do not: the kinds of people that have SCSI cards are the kinds of people that know the precise specifications of every component of their PC!
c) USB: USB (Universal Serial Bus) is a small port that has been included on most PCs since about 1998. It is a plug and play port, so installation is easy, and they are faster than parallel ports. They are also hot-swappable, meaning you can plug and unplug them when the PC is running, so this could be useful if you wish to use the scanner with more than one PC. If you do not have any USB ports free, you can buy a hub (like an adaptor to plug lots of USB devices into a single USB plug) for about £40, or if your PC does not have USB at all, you can buy a USB card to give yourself USB ports, for about £40, requiring a PCI expansion slot free. This is probably the most convenient way of connecting a scanner to a PC. The main drawback is simply that older PCs do not have USB and so you would have to fit a separate card to use it. Also bear in mind that Windows 95 was very limited in it's USB support: the first release, Windows 95a, did not support USB at all, whereas the next release, Windows 95b, did support it, but only with a "patch" upgrade, and even then, somewhat unreliably. For reliable USB connections, you must have Windows 98 or later.
d) USB2: This is an improved version of USB, above, which is much, much faster. The connectors are the same, so if you buy a USB2 scanner, but your computer only has USB1, then it will still work, but at the slower speed. Similarly, a USB1 scanner on a USB2 computer, will also work but at the slower speed.
So, to summarise:
- If your
computer has any USB ports, then get a USB scanner.
Some scanners do come with more than one connector, eg parallel and USB, which you may find useful if you plan to use the scanner with more than one PC, and some have different ports to others.
2) Scanning resolution. The resolution is the quality of the image the scanner can scan to, in dots per inch (dpi.) The higher the resolution, the better the image quality will be, but the larger the resulting files will be. If you only plan to use your scanner for basic photo scanning, to use as a photocopier, or for OCR (optical character recognition) then about 300-400 dpi is plenty, and all off-the-shelf scanners will be able to scan to this resolution. As very few domestic printers can print at a higher resolution than 300 dpi, it is pointless using a higher resolution. It is only if you wish to scan in very small images and then expand them, or wish to scan in photo negatives, that the higher resolutions are really necessary.
3) Document-handling features: Some expensive scanners also come with a multiple document feeder, like some expensive photocopiers have, for automatically feeding in large piles of pages. If you are planning on scanning in large numbers of pages one-after-another, them this could be useful to you.
4) Negative scanning: Some scanners have a built-in film adaptor unit, which allows you to scan in photo negatives and slides.
5) Bundled software: Check out what the scanner comes with. Most scanners will come with a basic image-editing program and a basic OCR (optical character recognition) package. However, some bundles are much more generous than others and therefore will impact on the product's value for money.
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