HP Designjet T1120 1118 mm User Manual

General advice
When you have any print-quality problem:
●To achieve the best performance from your printer, use only genuine manufacturers supplies and
accessories, whose reliability and performance have been thoroughly tested to give trouble-free
performance and best-quality prints. For details of recommended papers, see 
Order paper
on page 136.
●Make sure that the paper type selected in the front panel is the same as the paper type loaded into
the printer. To check this, use the View loaded paper key...

Alternatively, or if you have other print quality problems, you can continue reading this chapter.
Horizontal lines across the image (banding)
If your printed image suffers from added horizontal lines as shown (the color may vary):
1.Check that the paper type you have loaded corresponds to the paper type selected in the front
panel and in your software. To check on the front panel, use the View loaded paper key 
.
2.Check that you are using appropriate print-quality settings for your purposes (see...

Lines are too thick, too thin or missing
1.Check that the paper type you have loaded corresponds to the paper type selected in the front
panel and in your software. To check on the front panel, use the View loaded paper key 
.
2.Check that you are using appropriate print-quality settings for your purposes (see 
Printing
on page 55). Select the custom print-quality options in the driver dialog (Mac OS Print dialog), and
try turning on the Maximum detail option (if available). You may wish to reprint your...

3.Select the custom print-quality options in the driver dialog (Mac OS Print dialog), and turn on the
Maximum detail option (if available).
4.If you are using the PCL or HP-GL/2 driver for Windows, you can change your image rendering
resolution to 300 dpi or 600 dpi depending on your printing needs. You can find the Max.
Application Resolution option in the driver dialogs Advanced tab, under Document Options
> Printer Features.
Lines print double or in the wrong colors
This problem can have various...

1.Check that you are using appropriate print-quality settings. See Printing on page 55.
2.Reseat the printheads by removing them and then reinserting them. See 
Remove a printhead
on page 118 and Insert a printhead on page 121.
3.Align the printheads. See 
Align the printheads on page 172.
Lines are blurred
Humidity can cause ink to soak into the paper, making the lines blurred and fuzzy. Try the following:
1.Check that your environmental conditions (temperature, humidity) are suitable for high-quality...

Line lengths are inaccurate
If you have measured your printed lines and find that the lengths are not sufficiently accurate for your
purposes, you can try to improve line length accuracy in the following ways.
1.Print on HP Matte Film, for which your printers line length accuracy is specified. See 
Functional
specifications on page 190.
Polyester film is about ten times more dimensionally stable than paper. However, using film that is
thinner or thicker than HP Matte Film will reduce line length...

If the problem persists despite all the above actions, contact your customer service representative for
further support.
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 defects in the printed image, such as vertical stripes. This can happen when you use thin paper
that becomes saturated with ink.
1.Check that the paper type you have loaded corresponds to the paper type selected in the front
panel and in your...

Ink marks on the paper
This problem can occur for several different reasons.
Horizontal smears on the front of coated paper
If a lot of ink is used on plain or coated paper, the paper absorbs the ink quickly and expands. As the
printheads move over the paper, the printheads may come into contact with the paper and smear the
printed image. This problem is normally seen only on cut sheets of paper (not on roll paper).
Whenever you notice this problem, cancel the printing job immediately. Press the Cancel...

Edges of objects are stepped or not sharp
If edges of objects or lines appear to be poorly defined or lighter in density, and you have already set
the print-quality slider to Quality in the driver dialog (Mac OS Print dialog), select the custom print-quality
options, and try setting the quality level to Normal. See 
Printing on page 55.
Edges of objects are darker than expected
If edges of objects seem darker than expected, and you have already set the print-quality slider to
Quality in the driver dialog...

White spots on the print
You may notice white spots on the print. This is probably due to paper fibers, dust or loose coating
material. To avoid this problem:
1.Try cleaning the paper manually with a brush before printing, to remove any loose fibers or particles.
2.Always keep the cover of your printer closed.
3.Protect your paper rolls and sheets by storing them in bags or boxes.
Colors are inaccurate
If the colors of your print do not match your expectations, try the following:
1.Check that the paper...