Fine Adjustment Pattern; Fine Adjustment Pattern Detection - Epson Stylus Pro 4400 Service Manual

EPSON Stylus Pro 4400/4450/4800/4880/4880C

Fine Adjustment Pattern

This is a pattern for calculating the exact correction value. It uses all nozzles
and 3 Bi-D patterns are printed after being shifted by 1/1440 step for each
color. The location detected with the most raised A/D values and the 2
locations detected with the most lowered A/D values are averaged, and the
averaged values of the 3 patterns are calculated again, with the resulting value
set as the correction value.
Correction Value = {(A1+B2+C3/3) + (A2+B2+C2/3) + (A3+B3+C3/3)} / 3
A/D
Value
Figure 2-59. Fine Adjustment Pattern Detection
Operating Principles
Adjustment Lines Standard Lines
Most A/D values
are high
Most A/D values
are low
Scanning Position
Printer Mechanism Components
Revision C
150