Color
Another factor in your decision should be whether you will be scanning black and white and/or color images. This seems obvious, but the cost of color and black and white scanners ranges considerably, and if your intended use of the machine does not include reproducing color images, it would be prudent to focus on the key differences between the two types of scanners.

If you are planning on using your scanner solely as a data entry tool, you are best off focusing on the black and white market. As with color scanners, bit depth plays a key role in determining the quality of the machine.

A scanner with a bit depth of one can tell the difference between black and white and can handle scanning simple documents for OCR purposes. A bit depth of 12 can identify 4,096 gray scales and should be more than sufficient for the most complex black and white image.

If color is the key to your scanning needs be prepared for differences from the original image to the screen and printer. Because of different settings among various computer components, an image's colors rarely remain the same through the entire reproduction process.

Color calibration software can help align the differences by matching the color definitions of each device. Exact color matching should only be an issue for high-quality prints or other professional reproductions. In most cases quality color reproduction is adequate if exact color reproduction is not possible.