User manual

23 • WHITE POINT CALIBRATION
197
ColorQuartet 5.0 Pro
23•White point calibration
White point calibration
Why is it necessary
The output of the scanner’s light source changes slightly over time as the light source ages. If
compensation is not made for this physical characteristic of the system, the color balance of
your scans may begin to drift.
• To ensure consistent scanning results over a period of time, you should carry out a manual white
point calibration each day before starting work, as described below.
• ScanMate flatbed scanners automatically perform white point calibration before each scan.
However, daily manual calibration of the white point is still important, because it adjusts the
scanner to the current intensity of the light source and thus makes the automatic white point
calibrations go much faster.
• If you have a drum scanner, white point calibration should also be carried out each time you
mount a different drum.
How does it work
• Calibration balances the signals from the red, green and blue filters in the scanner. The signal
from each of the three filters is checked internally before a new scan pass is made.
• ScanMate scanners calibrate themselves for white by scanning a portion of clear glass (for
transmission) or a piece of white paper or other media (for reflection). The scanner uses the
result of this neutral “image” as a reference each time another scan is made.
White point calibrating your flatbed scanner
NOTE: before calibrating, make sure the standard mounting plate is in the scanner, not the
optional magnetic mounting plate system or (for ScanMate F8 Plus) the optional ScanDot
mounting plate.
1 • Choose Calibrate White from the Calibration menu.
2 • Click on OK to confirm.
White point calibration will automatically be carried out for both
transmission and reflection, and a message will appear to tell you
whether it was successfully completed.