Xerox CX240, User Manual

Page: 118 / 276

108 Chapter 7– Color Workflow
Calibration Overview
One of the most important issues in obtaining satisfactory print quality is
steady toner density. Toner density is affected by many factors such as
heat, humidity, and service settings. You should perform a daily
calibration to compensate for these factors.
The calibration process corrects the printer colors by measuring their
density and creating calibration look-up tables. The Spire CX250 color
server uses the data in these tables to compensate for the differences
between the actual, measured density and target levels; the target density.
You should perform calibration in the following instances:
•
When you use a new paper stock
•
At least once every eight hour shift for every combination of paper
stock and screening method used
•
When prints show “color casts”
•
After machine maintenance or hardware changes—for example,
replacing a photoreceptor
•
On drastic ambient changes (temperature and humidity)
There are two types of calibration:
•
Scanner calibration, see Scanner Calibration on page 109
•
Calibration using the X-Rite
®
DTP34 QuickCal densitometer (this
option is available only if you have the Pro configuration), see
Calibrating with the X-Rite DTP34 QuickCal Densitometer on page 112
Important: Perform a different calibration for every combination of media and
screen type you are going to use for printing. When calibrating, always use the
same media that you intend to use for printing.