Xerox Phaser EX7750 Reference Guide

Any misregistration between the different toners on paper causes color text to lose 
definition. You can make test prints to find the smallest point size at which color text 
prints clearly. When using high-end graphics applications that allow you to specify 
color as percentages of cyan, magenta, yellow, black, you can create pure cyan or pure 
magenta text that prints with the same sharpness as black text. (Pure yellow text is 
extremely hard to read on anything but a dark or complementary background.)

Two broad categories of artwork can be printed from a personal computer to a color 
printer:

.

A raster image, also referred to as a bitmap, is composed of a grid of 

, each 

assigned a particular color value (as illustrated in example a in the following figure). 
The grid, when sufficiently enlarged, resembles a mosaic made from square tiles. 
Examples of raster images include scans and images created in painting or pixel-editing 
applications, such as Photoshop and Corel Painter.

The resolution of a raster describes the compactness of the pixels and is specified in 
pixels per inch (ppi). The bit depth is the number of bits of information assigned to 
each pixel. Black and white raster images require only one bit of information per pixel. 
Grayscale images require 8 bits per pixel. For photographic quality color, 24 bits of 
RGB color information are required per pixel, yielding 256 levels of red, green, and 
blue. For CMYK images, 32 bits per pixel are required.

When printing raster artwork, the quality of the output depends on the resolution of 
the source raster. If the raster resolution is too low, individual pixels become visible in 
the printed output as small squares. This effect is sometimes called “pixelation.”

In 

, picture objects are defined mathematically as lines or curves 

between points—hence the term “vector” (see example b). Picture elements can have 
solid, 

, or patterned color fills. Vector artwork is created in illustration and