HP Designjet 4520 HD User Manual

							Lines are missing or thinner than expected
1.Check that the line thickness and color settings are correct in your application.
2.Check that you are using appropriate print quality settings. See 
Choose print quality settings
on page 57.
3.If the problem persists, clean the printheads. See 
Recover (clean) the printheads on page 97.
4.If the problem persists, use the Image Diagnostics Print to find out more about it. See 
How do I...
(Image Diagnostics Print topics) on page 117.
Solid bands or lines printed over the image
This kind of problem can show itself in several different ways, illustrated below in magenta:
1.A thick colored band
2.Thinner colored bands
3.Discontinuous colored blocks
4.Thin lines
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 printheads electrical connections on page 97.
2.Clean the printheads. See 
Recover (clean) the printheads on page 97.
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							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) on page 117.
Graininess
1.Check that you are using appropriate print quality settings. See Choose print quality settings
on page 57.
2.Use the Image Diagnostics Print to find out more about the problem. See 
How do I... (Image
Diagnostics Print topics) on page 117.
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.
Try changing to a heavier paper type: we recommend HP Heavyweight Coated Paper or HP Productivity
Photo Gloss for printing dense colors. See also 
Choose print quality settings on page 57.
The print smudges when touched
The black ink pigment can smudge when touched by a finger or pen. This is particularly noticeable on
the following materials: vellum, translucent bond, films, productivity photo paper and natural tracing
paper.
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							To reduce the smudging:
●Try to print in an environment which is not too humid for the printer. See 
Environmental
specifications on page 210.
●Change pure black objects in your image to a dark color, such as dark brown, so that they will be
printed with colored inks instead of black ink.
●Use HP Heavyweight Coated Paper.
●Increase the drying time (see 
Change the drying time on page 41).
Ink marks on the paper
This problem may occur for several different reasons.
Smears on the front of coated paper
If a lot of ink is used on coated paper, the paper absorbs the ink quickly and expands. As the printheads
move over the paper, the printheads come into contact with the paper and the printed image is smeared.
Whenever you notice this problem, you should cancel the printing job immediately. Press the Cancel
key and also cancel the job from your computer application. Otherwise the soaked paper may damage
the printheads.
Try the following suggestions to avoid this problem:
●Use a recommended paper type (see 
Supported paper types on page 200).
●If the image you are printing contains intense color, try using HP Heavyweight Coated Paper.
●Use extended margins (see 
Adjust the margins on page 59), or try to increase the margins by
relocating the image within the page using your software application.
●If necessary, try changing to a non-paper-based material such as transparent film.
Smears or scratches on the front of glossy paper
Glossy paper may be extremely sensitive to the bin or to anything else that it contacts soon after printing.
This will depend on the amount of ink printed and the environmental conditions at the time of printing.
Avoid any contact with the paper surface and handle the print with care.
Ink marks on the back of the paper
Ink residues on the platen or on the input rollers are likely to mark the back of the paper. See Clean the
platen on page 112 and Clean the input rollers on page 112.
Ink marks when the stacker is in use [4520]
NOTE:The stacker is available with the HP Designjet 4520 Printer series only.
Try the following suggestions:
●Clean the stacker roller. See 
Clean the stacker rollers on page 53.
●Check that the paper youre using is compatible with the stacker. See 
Using paper with the stacker
[4520] on page 201.
●When printing in Fast mode on Translucent Bond, Vellum or Natural Tracing Paper, there could be
some ink transfer marks in highly inked areas. Select Normal or Best mode to avoid this problem.
See 
Change the print quality on page 57.
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							A defect near the start of a print
There is a type of defect that affects only the start of a print, within 5.5 cm of the leading edge of the
paper. You may see a thin or thick band of inconsistent color:
To avoid this problem:
1.The easiest solution is to select the Extended Margins option in the driver, the Embedded Web
Server or the front panel. This means that the area of the paper affected by the problem (at the
start of the page) will no longer be printed on. See 
Adjust the margins on page 59.
2.Align the printheads. See 
Align the printheads on page 101.
3.Check that you are using appropriate print quality settings. See 
Choose print quality settings
on page 57.
Lines are stepped
If lines in your image appear stepped or jagged when printed:
1.The problem may be inherent in the image. Try to improve the image with the application you are
using to edit it.
2.Check that you are using appropriate print quality settings. See 
Choose print quality settings
on page 57.
3.Turn on the Maximum Detail option.
Lines are printed double or in wrong colors
This problem can have various visible symptoms:
●Colored lines are printed double, in different colors.
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							●The borders of colored blocks are wrongly colored.
To correct this kind of problem:
1.Align the printheads. See 
Align the printheads on page 101.
2.Check that you are using appropriate print quality settings. See 
Choose print quality settings
on page 57.
Lines are discontinuous
If your lines are broken in the following way:
1.Check that you are using appropriate print quality settings. See Choose print quality settings
on page 57.
2.You are more likely to get good vertical lines with roll paper than with sheet paper. If you must use
sheet paper, set the print quality to Best.
3.Consider changing to a heavier paper type, such as HP Heavyweight Coated Paper or HP
Productivity Photo Gloss. See
Choose print quality settings on page 57.
4.Align the printheads. See 
Align the printheads on page 101.
Lines are blurred (ink bleeds from lines)
If you see that the ink is soaking into the paper, making the lines blurred and fuzzy, this could be because
of humidity in the air. Try the following:
1.Check that your environmental conditions (temperature, humidity) are suitable for high-quality
printing. See 
Environmental specifications on page 210.
2.Try changing to a heavier paper type, such as HP Heavyweight Coated Paper or HP Productivity
Photo Gloss. See
Choose print quality settings on page 57.
NOTE:Glossy photo paper types are especially difficult to dry. Take extra care with them.
3.Check that the paper type selected in the front panel is the same as the paper type you are using.
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							4.Perhaps you have adjusted the drying time at the front panel to speed up the printer output. Select
the 
 icon, then  Select drying time , and make sure it is set to  Optimal.
5. Allow the prints time to dry separately; do not cover or stack them.
Lines are slightly warped
The paper itself may be warped. This can happen if it has been used or stored in an extreme
environment. See 
Environmental specifications on page 210.
Color accuracy
There are two basic requirements for color accuracy:
1.Ensure that your paper type has been calibrated, which will give you consistency from print to print,
and from printer to printer. See 
Perform color calibration on page 68.
2. Select suitable options in your application: see 
How do I... (color topics) on page 67.
NOTE: If you are not using PostScript, remember that your printer may be configured to use one of
its internal pen palettes instead of your softwares palette (which is the default). See 
Pen settings seem
to have no effect on page 165.
Color accuracy using EPS or PDF images in page lay out applications
Page layout applications such as Adobe InDesign and QuarkXPress do not support color management
of EPS, PDF or grayscale files.
If you have to use such files, try to ensure that the EPS, PDF or grayscale images are already in the
same color space that you intend to use later on in Adobe InDesign or QuarkXPress. For instance, if
your final goal is to print the job in a press that follows the SWOP standard, at the time of creating the
EPS, PDF or grayscale you should convert the image into SWOP.
PANTONE color accuracy
Spot colors are special premixed inks to be used directly in the press, and the best-known spot colors
are PANTONE colors.
If you have the PostScript model, your printer provides a facility called Automatic PANTONE Calibration,
which can easily match most of the PANTONE Solid Coated spot colors. When an application sends a
PANTONE color to print, it sends the PANTONE name together with its own estimate of equivalent
CMYK values. The Automatic PANTONE Calibration facility recognizes the PANTONE name and
converts it to CMYK in a way that depends on the printer model and the selected paper type, enabling
the color to be rendered with greater precision than is possible with the generic CMYK values sent by
the application.
Even when using Automatic PANTONE Calibration, you cannot expect the printer to match the
PANTONE colors exactly. Your printer is certified by Pantone for some papers, but this does not mean
that it can reproduce 100% of the PANTONE colors.
Using Automatic PANTONE Calibration (the best choice)
In order to use Automatic PANTONE Calibration, you need an application that recognizes the PANTONE
colors, and a calibrated PostScript printer.
The Automatic PANTONE Calibration facility emulates PANTONE Solid Coated colors only (suffix C).
Other PANTONE colors will be printed using the CMYK values sent by the application.
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							Converting PANTONE colors manually
If you have a non-PostScript printer, or if you are using an application (such as Adobe Photoshop) that
does not send the name of the PANTONE color to the printer, you will not be able to use Automatic
PANTONE Calibration. Instead, if you wish, you can convert each PANTONE color manually to CMYK
values in the application, using tables produced especially for your printer and paper type.
If your application has a facility to convert PANTONE colors to CMYK values automatically, it probably
does not take account of printer or paper type, so you will get better results with a manual conversion
using the tables.
You can also obtain a PANTONE calibrated color chart in EPS, TIFF and PDF format, which can be
convenient if your application has an eyedropper tool with which you can pick up colors from an imported
graphic.
Tips
●Automatic PANTONE Calibration works with PostScript printers only.
●Ensure that Automatic PANTONE Calibration is turned on in the driver.
●Some applications may not support PANTONE colors fully; for example, Photoshop 7.0 does not
send the PANTONE Color with its name, it sends only the CMYK values from its standard table.
●Some colors may be out of gamut and impossible to match precisely with your printer and paper
type.
Color matching between different HP Designjets
If you print an image on two different printer models (for instance, on an HP Designjet 4020 Printer series
and an HP Designjet 1000 Printer series), you may find that the colors of the two prints do not match
well.
Matching two printing devices that use different ink chemistry, paper chemistry and printheads is unlikely
to be completely successful. The information provided here is the best way to emulate one printer with
another. Even so, the end result may not be a perfect match.
Printing via separate PostScript drivers
The situation is that you are printing on each printer using the PostScript driver installed for that printer.
In this example, we are using an HP Designjet 4020 Printer series and an HP Designjet 1000 Printer
series.
1.Ensure that both printers have been updated to the latest firmware version. See 
Update my printers
firmware on page 116.
2.Ensure that you have the latest printer driver for both printers. You can download the latest drivers
for the HP Designjet 4020ps from 
http://www.hp.com/go/4020ps/drivers/.
3.Ensure that Color Calibration is turned on. At the front panel of the HP Designjet 4020 series, select
the 
 icon, then Printer configuration > Color calibration > On .
4.Load the printers with similar paper types.
5.Ensure that the Paper Type setting on the front panel corresponds to the paper you have loaded.
6.Print your image on the HP Designjet 1000 Printer series using your normal settings.
7.Now prepare to print the same image on the HP Designjet 4020 Printer series.
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							8.In your application, set the color space of the image to emulate the HP Designjet 1000 Printer
series and the specific paper type that you used in that printer. The data sent to the driver must be
already converted to this emulation color space, which is a CMYK color space. See your
applications online help for information on how to do this. In this way, the 4020 series will emulate
the colors that the 1000 series can produce when printing on that paper type.
9.In the PostScript driver for the HP Designjet 4020 Printer series, go to the Color Management
section and set the CMYK input profile to the same HP Designjet 1000 Printer series color space
that you selected in the application (the emulation color space).
NOTE:When trying to emulate another printer you should always use CMYK colors, not RGB.
10.Set the rendering intent to Relative Colorimetric, or to Absolute Colorimetric if you want to emulate
the whiteness of the paper.
11.Print the image on the HP Designjet 4020 Printer series.
Printing via separate HP-GL/2 and HP RTL drivers
The situation is that you are printing on each printer using the HP-GL/2 and HP RTL driver installed for
that printer.
1.Ensure that both printers have been updated to the latest firmware version. See 
Update my printers
firmware on page 116.
2.Ensure that you have the latest printer driver for both printers. You can download the latest drivers
for the HP Designjet 4020 from 
http://www.hp.com/go/4020/drivers/.
3.Ensure that Color Calibration is turned on. At the front panel of the HP Designjet 4020 Printer series,
select the 
 icon, then Printer configuration > Color calibration > On .
4.Load the printers with similar paper types.
5.Ensure that the Paper Type setting on the front panel corresponds to the paper you have loaded.
6.With the HP-GL/2 and HP RTL driver for the HP Designjet 4020 Printer series, select the Color tab,
and select Printer Emulation from the list of color management options. Then choose the
Designjet 1000 series from the list of emulated printers.
7.With the HP-GL/2 and HP RTL driver for the HP Designjet 1000 series, select the Options tab,
then Manual Color > Color Control > Match Screen. You should also select the Paper Size tab,
then Paper Type.
Printing the same HP-GL/2 and HP RTL file
The situation is that you have produced an HP-GL/2 and HP RTL file (also known as a PLT file) using
the HP-GL/2 and HP RTL driver installed for one printer, and you intend to send the same file to both
printers.
1.Ensure that both printers have been updated to the latest firmware version. See 
Update my printers
firmware on page 116.
2.Ensure that Color Calibration is turned on. At the front panel of the HP Designjet 4020 Printer series,
select the 
 icon, then Printer configuration > Color calibration > On .
3.Load the printers with similar paper types.
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							4.Ensure that the Paper Type setting on the front panel corresponds to the paper you have loaded.
5.If you have an HP-GL/2 and HP RTL file produced for an HP Designjet 1000 Printer series and you
want to print it on an HP Designjet 4020 Printer series, proceed as follows using the Embedded
Web Server or the front panel.
●Using the Embedded Web Server: leave the color options set to Default.
●Using the front panel: select the 
 icon, then Default printing options > Color options >
Select RGB input profile > HP Designjet 1000 Series.
For other HP Designjet printers, set both printers to match the screen colors (sRGB if selectable),
as when printing with separate HP-GL/2 and HP RTL drivers.
Improving gray neutrality
There are two ways to improve the gray neutrality in printed plots:
●Use the setting Optimized Gray Neutrality, which is applicable to HP-GL/2 and HP RTL files only.
This setting will mainly improve the neutrality of the light gray area fills by changing the ink
composition of the gray areas, putting more black ink and less color ink (the area fills will be printed
with less composite colors, and with more black ink only). One possible side effect: the image
quality may be reduced as less composite color ink is used to print. If this happens, try selecting
better image quality settings (for example, changing from Normal to Best), or doing only the visual
gray calibration without enabling optimized gray neutrality.
●Use a specific Visual Gray Calibration, applicable to any file format.
This calibration can be performed from the front panel by printing some gray patterns of different
neutrality, and by selecting the best one. This calibration is optimized for one specific image quality
setting and specific paper. So it is very important, before printing the pattern, to set, within the front
panel, the default image quality settings that you normally use and to load the right paper type. If
you are using different image quality settings and different papers, different calibrations have to be
done, one calibration for each image quality setting and paper.
The two calibrations are independent, and can be applied both at the same time, or only one. When
setting the Optimized Gray neutrality, and doing a visual calibration, finding the difference between
the different color patterns can be difficult. Just select the one that is nearest your preference.
Optimized gray neutrality calibration
To select optimized gray neutrality for HP-GL/2 and HP RTL prints.
1.
On the printers front panel, select 
then Default printing options > HP-GL/2 Options >
Optimized Gray Neutrality.
2.Select when you want the setting applied from one of the following options:
●Never (default option)
●Drawings/text only
●Images only
●Always
Example: If you select Drawings/text only, optimized gray neutrality will be applied only if, within
the image quality settings of the plot sent, Optimized for is set to Drawings/text.
3.Please validate this setting with some sample gray plots before performing the visual gray
calibration described in next section.
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							NOTE:This option only applies to HP-GL/2 and HP RTL prints and it is designed to improve
medium to low density gray area fills.
Visual gray calibration
This calibration will be optimized for the Image Quality options that are selected in the front panel at the
time the calibration is done.
1.It is important to select from the front panel menu the image quality settings you normally use.
Select the 
 icon, then Default Printing Options > Image quality.
●Select print quality: (Best, Normal, Fast).
●Select optimize for: (Drawings/text, Images).
●Enable maximum detail: (On, Off).
2.Make sure that the paper loaded is the paper on which you want to print the neutral gray.
3.Print the first pattern to select the best gray, go to the front panel, select the 
 icon, then
Printhead > Visual gray calibration > Print first pattern.
4.The pattern will contain a set of images printed with different corrections of CMYK, if one of these
patterns provides the desired gray neutrality go to step 6, if there is not an exact match, choose
the number of the pattern closest to the desired gray neutrality.
5.Print the second pattern that you select from the previous step, identify the closest pattern to the
gray neutrality you want:
●Print pattern 1
●Print pattern 2
●Print pattern 3
●Print pattern 4
●Print pattern 5
●Print pattern 6
●Print pattern 7
6.Enable the calibration: Select the 
 icon, then Printhead > Visual gray calibration > Enable
calibration.
7.Enter the CMYK values printed on the selected pattern into in the front panel menu: Select the
 icon, then Printhead > Visual gray calibration > Select Pattern.
Some cautionary notes
When using the above procedure bear in mind the following information:
●The process applies the CMYK correction to all paper types loaded, and to all image quality
settings, but it can guarantee gray neutrality only for the paper type and front-panel print-quality
settings that were used while doing the calibration. The calibration should be run again with any
other print-quality settings and paper types that you might use (one calibration per print-quality
settings + paper).
●If you change the printheads, you should recalibrate.
●When selecting the different gray patterns, make sure that you use the lighting conditions in which
you want the final image to be viewed, fluorescent light or sunlight for example.
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