Canon iR C6800 Series Service Manual page 297

*1: Differences Among 3 Test Patterns
Test Print 1
It shows 64 gradations expressed by means of error diffusion processing, which is not subject to moire and, therefore,
used in text/photo/map, print photo, and text mode.
Test Print 2
It shows 64 gradations expressed by means of screening with a low num ber of lines, which is suitable for the
expression of gradation and, there fore, is used for print film photo mode and when priority is placed on PDL.
Test Print 3
It shows 64 gradations expressed by means of screening with a high number of lines, which is suitable for the
achievement of a high resolu tion and is, therefore, used when priority is placed on PDL resolution.
F-7-26
Test Print
Chapter 7
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