Microtek ScanMaker 6100 Pro User Manual page 114

together, while lighter areas are those with scattered dots. An
example of halftone images would be the pictures you see in a
newspaper or magazine.
Grayscale
Grayscale images contain more than just black and white, and
include actual shades of gray. In a grayscale image, each pixel has
more bits of information encoded in it, allowing more shades to be
recorded and shown.
For instance, four bits are needed to reproduce up to 16 levels of
gray. Going higher, eight bits can reproduce the 256 levels of gray
required to represent most black-and-white photos accurately.
Color
Color images contain the most complex information. To capture
color images, scanners use a process based on the RGB (Red,
Green and Blue) color model, where every color is composed of a
varying amount of the three colors. In the RGB model, the absence
of white light creates black, the complete saturation of light creates
white (100% if red, green, and blue), and equal amounts of red,
green, and blue create intermediate shades of gray.
Depending on the type of scanner you have, your scanner can
record 24 bits for the three RGB channels. This means your scanner
can record and reproduce an enormous amount of color information
- anywhere from 16.7 millions colors for 24-bit scanners.
Selecting an image type
Depending on the scanner you have, you will be able to scan
different types of images according to your needs. You can scan an
image and output it in its original form, or you can output it in
another form and get some interesting effects.
For instance, you can scan a color photo and output it in its original
form as a color photo, or you can output it as a gray to create a