Maintenance; Calibrating The Printer/Copier; Visualcal Calibration - Xerox DocuColor DocuColor 4 User Manual

6.2.3

Maintenance

Problems such as streaking and insufficient or excessive amounts of one or
more Dry Inks arise when a print device does not receive periodic mainte-
nance. In addition to having it serviced regularly, monitor the color produc-
tion of your printer/copier by making standard test prints at regular inter-
vals. You can do this easily by printing the DocuColor 4 LP/CP Test Page
from the control panel. Save the prints and show them to your system or site
administrator if recalibration becomes necessary.
6.2.4

Calibrating the printer/copier

Device consistency can be maintained through regular calibration of the
printer/copier.
6.2.5

VisualCal calibration

VisualCalTM is a calibration method that allows you to recalibrate your
printer/copier to an ideal color output standard. The calibration calculations
performed by the controller software are based on a series of values entered
on the control panel. The values used in the calculations are determined by
evaluating Dry Ink densities and color combinations produced on two spe-
cially designed calibration pages printed from the control panel.
Limits and 30% Match
The first VisualCal page, "Limits and 30% Match," provides the basis for
calculating the most acceptable luminosity (brightness) of the Dry Inks. This
page consists of rows of CMYK dots in a graduated range of Dry Ink densi-
ties.
The variables needed to recalculate the density of the colored Dry Inks are
determined by identifying the leftmost dots that can be fully distinguished
against their fields in each row, and sequentially entering their correspond-
ing numeric values on the control panel. The variable needed to recalculate
the luminosity of the Dry Inks is determined in a slightly different way-you
identify the black dot which best matches a 30% dot gain field. When all
values have been entered, the printer's Dry Ink density and luminosity set-
tings are recalculated.
6.2 Controlling printed color
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