Pentax 3 User Manual page 71

The image is compressed and stretched in many places
Make sure the release cover was not left open during printing. If it is
open, close it completely.
Make sure the paper is not slipping in the printer. If it is, make sure the
print head and platen roller are clean. See Chapter 4, "Maintaining the
Printer."
Make sure the paper is not wrinkled prior to inserting it. Also, make
sure you are using Pentax Quality paper.
The image has light or white vertical lines
Make sure the release cover was not left open during printing. If it is
open, close it completely.
Clean the print head. Follow the instructions in "Cleaning the Print
Head," page 45.
If cleaning the print head does not correct the problem, the print head
may need maintenance. Call technical support.
All pages have a white vertical line
The print head may need maintenance. Call technical support.
All pages have a black vertical line
The print head may need maintenance. Call technical support.
Light patches of print appear on the image
The printer requires smooth paper to work properly. Make sure the
paper does not have any dents or wrinkles. It should lie flat and it
should not have a defective or uneven surface coating. Use Pentax
Quality paper and make sure it does not have any obvious deformities.
Check the density setting using the printer driver. If the setting is too
low, raise it. See page 17, "Making Prints Lighter or Darker."
Clean the print head. Follow the instructions in "Cleaning the Print
Head," page 45.
If using a DC power adapter, make sure the voltage from the vehicle is
high enough. Try starting the engine if necessary.
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