Choosing the Right Scanner
Given below are some tips on choosing the right scanner.
Q. What should one look for while buying a scanner?
A. While buying a scanner, one should look for the following:
- Bit depth (Pixel depth): The greater a scanner’s bit-depth, the more information it is able to record about each pixel it sees. A 24-bit colour scanner can register up to 16 million discreet graduations. This level of colour reproduction has become the standard for most office or web applications.
- Resolution: True Optical resolution is far more important than the Interpolated resolution. The true optical resolution of a scanner is determined by the quality of the CCD cell readings taken, i.e. dots per inch (DPI), and by the optical system. When comparing scanners, check whether their optical resolution is true or software enhanced i.e. Interpolation. Interpolated resolution captures no additional detail, it only helps in the enlargement of a scan.
- Interface: The two most common types of scanners sold are the Parallel and USB. If your computer does not have a USB port, then it may be more cost effective to purchase a parallel scanner to avoid having to put in a new USB port.
The other concern with USB and older computers is in Windows. USB and Windows 95 do not work well together. So, if you are going for a scanner having a USB interface, it is recommended that you run Windows 98 or higher. The advantage of USB over Parallel is that it tends to be a little faster, and less likely to collide with other hardware on your computer. Hundreds of USB devices can work together without conflicts or performance loss. Parallel on the other hand works best when there is a dedicated parallel port for each device. In most instances parallel scanners require you to share the same port as the printer, where the printer is connected to the back of the scanner as a pass through, in most cases this works fine. It is not recommended to run more than two devices on one parallel port.
Firewire and SCSI interface scanners are great for those who scan frequently and want high end performance in terms of speed and reliability. The only downside to both Firewire and SCSI is that the both require a controller card to operate and tend to be more expensive.
Q. What is the ideal configuration for a scanner?
A. Depending on your usage, the points below may guide you in selecting a suitable scanner:
- For a scan job that is meant to output to an ink-jet colour printer or desktop laser printer, a 600dpi flatbed scanner will be excellent for the job, although, a 400dpi unit may be an adequate and much less expensive option.
- For a scan job that is meant for a screen i.e. webpage, a 300dpi flatbed scanner is more than adequate.
- If you want large sheets of documents or high quality images to be scanned drum scanner is the ideal choice, as their scan quality is superior to their flatbed counter-parts.
- If you are constantly on the move because of your work then hand-held scanner is the ideal choice as they are portable, can be directly plugged into your laptops, or even to your PC printer port and gives reasonably good quality scanned images.
Q. Links to other sites for information on scanners.
A. The following are the few popular sites which can provide more information on scanners: