HP Designjet 4500 Printer series - Manual (Page 276)

In each case the recommended procedure is as follows:
1. Clean the electrical connections of the printhead that seems to be responsible (in this example,
the magenta printhead). See Clean a printhead's electrical connections.
2. Clean the printheads. See Recover (clean) the printheads.
3. Reprint your image with the same settings as before.
4. If the problem persists, replace the printhead that seems to be causing the problem. If you are
not sure which printhead is responsible, use the Image Diagnostics Print to identify it. See How
do I... (Image Diagnostics Print topics).
Graininess
1. Check that you are using appropriate print quality settings. See Choose print quality settings.
2. Use the Image Diagnostics Print to find out more about the problem. See How do I... (Image
Diagnostics Print topics).
The paper is not flat
If the paper does not lie flat when it comes out of the printer, but has shallow waves in it, you are
likely to see visible defects in the printed image, such as vertical stripes. This can happen when you
use thin paper that becomes saturated with ink.
262 Chapter 18 The problem is... (print quality topics) ENWW
The problem is... (print
quality topics)