What types of
scanning are there?

When you scan an image, you can tell the computer what type of image it is, and what technique should be used for scanning it. The most common scanning modes are:

• line art (also called black-and-white)
• grayscale
• color

You select the scanning mode based upon the graphic you are scanning.

Line Art - Choose line art when your graphic is pure black and white, with no shades of gray. This is a good setting for sketches, cartoons, blueprints, diagrams, black and white logos, etc.

Scanning a file as line art saves lots of space, because a pixel can only be black or white; the computer doesn't need to store lots of color information. Since there is a sharp demarcation between black and white it is possible that the scanned image may have slightly jagged edges; to decrease this effect, increase the resolution of the scan or scan in grayscale.

Grayscale - Choose grayscale when your graphic has shades of gray as well as black and white. Grayscale scanning will record up to 256 shades of gray, and so the transition from white to black is smooth. This is the best choice for black and white photos.

With grayscale images, each pixel can store one of 256 different shades, making grayscale images much larger than line art.

Color - Choose color when you are scanning a color graphic or photograph.

When you scan in color, each pixel can store one of millions of different colors. As you can imagine, color scans take up the most disk space.

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All rights reserved. This material may not be used without written permission.
Contact Dr. Mary Nicholson at mjnich@bloomu.edu