HP LaserJet 4345 Multifunction Printer series - Manual (Page 192)

Calibrating the scanner
Calibrate the scanner to compensate for offsets in the scanner imaging system (carriage
head) for ADF and flatbed scans. Because of mechanical tolerances, the scanner's carriage
head might not read the position of the image accurately. During the calibration procedure,
scanner offset values are calculated and stored. The offset values are then used when
producing scans so that the correct portion of the document is captured.
Scanner calibration should be carried out only if you notice offset problems with the scanned
images. The scanner is calibrated before it leaves the factory. It needs to be calibrated again
only rarely.
Before calibrating the scanner, print the calibration target.
To print the calibration target
1. Place letter- or A4-size paper in tray 1, and adjust the side guides.
2. Touch DIAGNOSTICS
3. Touch CALIBRATE SCANNER.
4. Print the first pass of the calibration target.
5. Place the first pass of the calibration target in tray 1 so that the arrows are facing into the
MFP.
6. Print the second pass. The final calibration target must look like the following figure.
CAUTION If the calibration target does not look like the figure shown here, the calibration process will
fail and the quality of scans will be degraded. The black areas must extend completely to the
short edges of the page. If they do not, use a black marker to extend the black areas to the
edge of the page.
7. Place the calibration target face-up into the ADF, and adjust the side guides.
8. Touch Menu, touch DIAGNOSTICS, then touch CALIBRATE SCANNER.
9. After the calibration target has passed through the ADF once, reposition it in the ADF in
the opposite direction. After the second pass, the calibration is complete.
178 Chapter 9 Managing and maintaining the MFP ENWW