Scanner Shopping Guide

What is a Scanner?Scanners are similar to digital cameras, except cameras can focus into infinity. Desktop scanners have physical dimensions that determine the size and bulk of the material that can be scanned.  Scanners usually come with software, such as Adobe's Photoshop product, that lets you resize and otherwise modify a captured image. Scanners usually attach to your personal computer with a Small Computer System Interface (SCSI). An application such as PhotoShop uses the TWAIN program to read in the image.  Scanners are rated in dots per inch (dpi), whereas cameras are rated in total pixels. Both scanners and cameras have an optical resolution (the real lens resolution) and an interpolated resolution computed by software.

Looking for function in Scanners.

• Resolution: Scanner resolution (the sharpness of text and images on paper) is usually measured in dots per inch (dpi). Most inexpensive scanners provide sufficient resolution for most purposes.

• Speed: If you do much scanning, the speed of the scanner becomes important. Inexpensive scanners scan about 3 to 4 sheets per minute. More expensive scanners are much faster.

• Memory: Most scanners come with a small amount of memory (for example, one megabyte) that can be expanded by the user. Having more than the minimum amount of memory is helpful and faster when scanning larger or more detailed images.

What is SCSI?SCSI (Small Computer System Interface) is a set of ANSI standard electronic interfaces that allow personal computers to communicate with peripheral hardware such as printers and scanners faster and more flexibly than previous interfaces.  SCSI uses a bus structure and functions like a mini-LAN connecting 16 devices, but the host adapter counts as one device. SCSI allows any two devices to communicate at one time (host to peripheral, peripheral to peripheral).

What are Scanner Drivers?Scanner drivers are a program that controls a scanner. Whenever you scan a document, the scanner driver takes over, feeding data to the scanner with the correct control commands. Most modern operating systems come with scanner drivers for the most common types of scanners, but you must install them before you can use the scanner. You can also download updated scanners from the scanner manufacturer's web site. A scanner comes in a range of different prices. You can find many discount scanners from as little as Rs.1600 to over Rs.80,000. Price ranges for scanners general depend on total functions, speed and scan quality.  There are many quality manufacturers of scanners, but some of the best selling are like HP (Hewlett Packard), Epson, Visioneer, Microtek, Umax, Mustek or Canon.