Print Quality - Partshere.com

Print Quality
6
6
Print Quality 6-2
Print Quality Troubleshooting Actions 6-2
How to Use the Service Image Quality Diagnostic Print 6-3
What is the Service Image Quality Diagnostic Print? 6-3
Considerations for Printing the Diagnostic Print 6-4
Printing the Service Image Quality Diagnostic Print 6-4
Diagnostic Part 1: Printhead Problems 6-6
Diagnostic Part 2: Alignment Test 6-7
Diagnostic Part 3: Printheads & Paper Advance Test 6-8
No Printing Defects Found in the Diagnostic Print 6-9
Printing the Advance Diagnostics Print 6-10
Advanced Diagnostic: Paper Advance Print 6-11
Advanced Diagnostic: Visual Alignment Diagnostic Print 6-14
Advance Diagnostic: Visual Nozzle Health. 6-16
Advance Diagnostic: Force Drop Detection 6-17
Print Quality General Advice 6-18
Troubleshooting Print Quality Problems 6-18
Horizontal Lines Across the Image (Banding) 6-18
Lines are Missing or Thinner than Expected 6-19
Problems with Stepped Lines 6-19
Lines are Printed Double or in Wrong Colors 6-20
Lines are discontinuous 6-21
Lines are Blurred (Ink Bleeds from Lines) 6-21
Problems with Graininess 6-22
Paper is not Flat 6-23
Print Scuffing or Scratching when Touched 6-24
Ink marks on the paper 6-24
Problems with the Edges of objects 6-25
Bronzing 6-26
Black and white prints do not look neutral 6-26
Horizontal lines at the end of a cut sheet print 6-26
Vertical lines of different colors 6-26
White spots on the print 6-26
Problems with Color Accuracy 6-27
Output Only Contains a Partial Print 6-27
Problems with Image Clipping 6-28
Some objects are missing from the printed image 6-28
A PDF file is clipped or objects are missing 6-29
HP Designjet Z3100/Z2100 GP Photo Printer Series — Service Manual
6-1
Print Quality
Print Quality
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Print Quality Troubleshooting Actions
For some Print Quality problems, a Call Agent can try and
troubleshoot the Printer by requesting the Customer to
perform certain actions. Using this process, most problems
can resolved without the need of an on-site visit.
When faced with a Print Quality problem, perform the following actions in
order to resolve the problem:
1 Printer Configuration:
„ Check that the paper type selected in the Front Panel is the same as the
paper type loaded into the Printer.
„ Make sure that the correct Print Quality settings are used for different
types of print content. Refer to Page 6-2 for further information.
„ Dry time should be set to “Optimal”.
2 Perform Printhead recovery (Main Menu/Image Quality Maintenance/
Clean Printheads).
3 Media:
„ Select the correct media type through the front panel when loading it.
„ Make sure that HP or HP-approved media is being used.
4 Perform the Printhead Alignment (Main Menu/Image Quality Maintenance/
Align Printheads).
5 Check if the latest version of the firmware is installed. If not, install the latest
firmware revision.
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HP Designjet Z3100/Z2100 GP Photo Printer Series — Service Manual
Print Quality
How to Use the Service Image Quality Diagnostic Print
What is the Service Image Quality Diagnostic Print?
The Printer contains an internal Image Quality Test which helps you to
diagnose the possible source of any image quality defects. The Service IQ
Diagnostic Print is available in the following options:
1 Image Quality Service Best Plot. This plot helps you to diagnose in more
detail the possible source of any image quality defects. It is accessible
through the Service Utility Menu.
The Image Quality Service Best Plot uses the Best Print Mode and is divided
in to three parts as follows:
„ Printhead Reliability Test. The purpose of this test is to identify which
Printhead is faulty.
„ Printhead Alignment Test. This test is designed to check any color-to-color
and bi-directional misalignment the printer may have.
„ Printheads and Media Advance test. This test is designed to check
whether the Printheads and the Media Advance Mechanism are working
correctly.
2 Image Quality Service Normal Plot. This plot is the same as the Image
Quality Service Best Plot but uses the Normal Print Mode.
3 Advanced Diagnostic Plot. These tests provide more information of the IQ
defects that we could find in the Image Quality Service plot.
The Advanced Diagnostic Plot is divided into the following parts:
Visual Media Advanced Diagnostic. Used to check advance reliability.
Visual Alignment Diagnostic. Used to check pen alignment reliability.
Visual Nozzle health Diagnostic. Used to check nozzle health reliability.
Force Drop Detection. Used to reset the nozzle health historic data base
and force new drop detection.
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HP Designjet Z3100/Z2100 GP Photo Printer Series — Service Manual
6-3
Print Quality
Considerations for Printing the Diagnostic Print
1 The IQ Diagnostic Print prints in A3 and B sizes so you must have media
loaded (roll or sheet) that is this size or larger.
2 Use the same type of media that the customer was using when they found
the image quality problem.
3 If the customer is using non-HP media and after the Image Quality Test you
still have the same image quality problems, change to genuine HP media
and repeat the Image Quality Test.
4 If you do not see any problems with the Image Quality Test, then the
problem may not be with the printer itself. The problem may be with the RIP
or the driver for example.
However, if you do see problems with the Image Quality Test then continue
with the Advanced Diagnostic procedures which will help you to diagnose
the problem.
Printing the Service Image Quality Diagnostic Print
1 In the Service Utilities submenu, scroll to “Diagnostic Print” and press OK.
Press OK
2 You will be given three options. Use the Arrow keys to make the selection
and press the OK key to start printing the required Diagnostic Print or to
enter the Advanced Diagnostics menu.
Press OK to
confirm selection
Use UP and
DOWN keys
to select
3 If you selected the Advanced Diagnostics Prints in the previous step, use the
Arrow keys to make the required selection Paper Advance, Visual
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HP Designjet Z3100/Z2100 GP Photo Printer Series — Service Manual
Print Quality
Alignment Diagnostic, Nozzle Health, Force Drop Detection or Print Banding
Plot, and press the Enter key to start printing.
Use UP and
DOWN keys
to select
Press OK to
confirm selection
4 Make sure media is loaded, the Media Lever is lowered and that the Ink
System is correctly installed. Press the OK key to print the Diagnostic Print or
press Back/Cancel to exit without printing the Diagnostic Print.
Press Cancel
or the Back
key to Exit
Press OK to
print
5 The selected Diagnostic Print will now be printed.
HP Designjet Z3100/Z2100 GP Photo Printer Series — Service Manual
6-5
Print Quality
Diagnostic Part 1: Printhead Problems
The Nozzle print Test test is designed to check if the Printhead nozzles print
correctly.
The nozzles check (bottom of the plot) is printed in a one-pass full swath
mode. The diagnostics test prints out every single nozzle of each Printhead
without applying an error hiding or alignment algorithm.
For each Printhead, you can see both the adjacent and the consecutive
nozzles.
If any nozzles not printing correctly they will be shown on the right of each
Printhead Nozzle test. There is a series of numbered stepped diagonal lines.
If one or more of the nozzles are malfunctioning or mis-positioned, you will
see that the stepped lines are broken or misdirected in one or more places.
Corrective Action
If the printer has nozzle defects, it does not mean that you will not get
perfect print quality results because the Printer can automatically
compensate for this so there is no need to replace the Printhead.
The method of improving Nozzle Defects is to:
1 Recover the Printheads, using the Front Panel Main Menu/Image Quality
Maintenance/Clean Printheads option.
2 Reprint the Printhead Nozzles Test Plot to verify that the defective nozzles
have been corrected.
3 If the problem continues, replace the defective Printhead.
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HP Designjet Z3100/Z2100 GP Photo Printer Series — Service Manual
Print Quality
Diagnostic Part 2: Alignment Test
This test is designed to check any color-to-color and bi-directional
misalignment the printer may have.
1 If the Printer is experiencing horizontal misalignment problems, the
Alignment Test will show something like this:
2 If the Printer is experiencing vertical misalignment problems, the Alignment
Test will show something like this:
3 If the Printer is experiencing bi-directional misalignment problems, the
Alignment Test will show something like this:
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Print Quality
Corrective Action
Perform a Printhead Alignment, using the same paper type with which you
were experiencing unacceptable image quality, if feasible (some paper
types are not suitable for Printhead Alignment).
Diagnostic Part 3: Printheads & Paper Advance Test
This test is designed to check whether the Printheads and the Paper Advance
Mechanism are working correctly. This part of the Image Quality Test should
not be used to check for color consistency or accuracy.
Banding
If the Printer is experiencing a banding problem, you will see repetitive
horizontal bands within the printed image.
„ Dark line banding repeated along the band (from top to bottom at the
same distance).
„ White line banding repeated along the band (from top to bottom at the
same distance).
The plot is printed in Best or Normal mode (according to the menu option
selected) with Error Hiding ON. The first top band has 100% ink density
patches while the bottom band has 50% ink density.
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HP Designjet Z3100/Z2100 GP Photo Printer Series — Service Manual
Print Quality
Troubleshooting Banding Problems
If banding does not occur in ALL the colors, then it is more than likely a
Printhead problem. In this case, try the following:
1 Check that the appropriate print quality settings are being used.
2 Recover the printheads using the option through the Front Panel (Main
Menu/Image Quality Maintenance/Clean Printheads). Reprint the
Diagnostic Print or the print file and if the problem persists, replace the faulty
Printhead.
If banding does occur in ALL the colors, then it is more than likely a Paper
Advance problem:
„ If the bands are light, it means that the paper has advanced too much.
„ If the bands are dark, it means that the paper hasn’t advanced enough.
„ In high quality modes, graininess in ALL colors can indicate problems
either with alignment or Paper Advance.
In order to solve any of these problems, try the following:
1 Check that the appropriate print quality settings are being used.
2 Check that the loaded media is the same type as selected in the printer.
Verify this using the option through the Front Panel (Main Menu/Paper
menu/View loaded paper).
3 If the customer is using low quality paper, try recommending better quality
paper (preferable HP paper). Printer performance can only be guaranteed
by using recommended papers.
4 Perform the Paper Advance Calibration using the same type of paper that
will be used for the final print.
If there is white point banding in only one color band and the problem
cannot be fixed using the Printhead recoveries, in some cases using the force
a drop detection option can fix this issue (see Advance Diagnostics: Force
Drop Detection).
No Printing Defects Found in the Diagnostic Print
If all the test patterns from the Diagnostic Print are correct and you still
experience Image Quality problems, you can use the following procedures
to resolve the problem.
„ Print Visual Media Advance Diagnostic
„ Print Visual Alignment Diagnostic
„ Print Visual Nozzle Health Diagnostic
„ Force Drop Detection
HP Designjet Z3100/Z2100 GP Photo Printer Series — Service Manual
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Print Quality
Printing the Advance Diagnostics Print
1 In the Service Utilities submenu, scroll to “Diagnostic Print” and press OK.
Press OK
2 You will be given three options. Use the Arrow keys to select the Advanced
Diagnostics menu.
Press OK to
confirm selection
Use UP and
DOWN keys
to select
3 From the displayed options, use the Arrow keys to make the required
selection Paper Advance, Visual Alignment Diagnostic, Nozzle Health,
Force Drop Detection or Print Banding Plot, and press the Enter key to start
printing.
Press OK to
confirm selection
6-10
Use UP and
DOWN keys
to select
HP Designjet Z3100/Z2100 GP Photo Printer Series — Service Manual
Print Quality
4 Make sure media is loaded, the Media Lever is lowered and that the Ink
System is correctly installed. Press the OK key to print the Diagnostic Print or
press Back/Cancel to exit without printing the Diagnostic Print.
Press Cancel
or the Back
key to Exit
Press OK to
print
5 The selected Advanced Diagnostic Print will now be printed.
Advanced Diagnostic: Paper Advance Print
This plot helps you to visually check any alignment problems of the printer.
You use it to precisely measure the media advance error with a one dot row
accuracy, and to verify the stability of the media advance.
The whitest vertical line should be positioned in the 0 offset column with
minor variations between +2 and -2 columns. If the offset is not positioned
on the 0 column or between +2 and -2 columns and the whitest vertical
varies a lot the printer requires media advance recalibration.
It is very important to verify that the loaded media is the
same media type as selected in the front panel. Verify this
using the option through the Front Panel (Main Menu/Paper
menu/View loaded paper). The wrong type of paper
selected will produce an offset error in the Visual Media
Advance print.
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Print Quality
The following plot shows correct media advance, there is a straight white
line positioned close to the 0 column for the majority of the points.
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HP Designjet Z3100/Z2100 GP Photo Printer Series — Service Manual
Print Quality
The following plot shows a bad media advance, there is a straight white line
positioned close to the -6 column, instead of the 0 column for the majority of
the points.
HP Designjet Z3100/Z2100 GP Photo Printer Series — Service Manual
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Print Quality
Advanced Diagnostic: Visual Alignment Diagnostic
Print
This plot helps you to visually check any alignment problems of the printer.
You use it to precisely measure the alignment error with a one dot row
accuracy.
To ensure you obtain meaningful results, use the same type
of media that the customer was using when they
encountered the image quality problem
For the printer to be considered correctly aligned, the results must be within
±1 dot row.
The illustration shows the complete Visual Alignment Diagnostic print that
identifies each of the specific alignment test results covered.
a
b
c
d
e
f
The Visual Alignment Diagnostic print shows the following diagnostic test
results:
a odd2even_SAD: Horizontal direction in forward and reverse.
b pen2pen_SAD: Horizontal direction.
c PAD
d pen2pen_bidir_SAD: Horizontal bi-direction.
e color_bidir_SAD: Horizontal bi-direction.
f thetaZ and VLS: only contour part (dark bands).
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HP Designjet Z3100/Z2100 GP Photo Printer Series — Service Manual
Print Quality
The following plot shows correct visual alignment, the lightest band is
positioned on the 0 column.
For the thetaZ and VLS diagnostics the dark band of the print is the area to
check. In the following example print the lightest segment of the dark band is
positioned on the -1 column.
Dark band
If the customer is using non-HP media and after the Image Quality Test you
still have the same image quality problems, change to genuine HP media
and repeat the Image Quality Test. The best alignment calibration is
obtained using HP Photo Paper.
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Print Quality
Advance Diagnostic: Visual Nozzle Health.
The print contains three separate parts.
a
b
c
a The Variable Frequency Nozzle health plot with odd/even nozzles
separation. This is used to detect misdirected or weak nozzles, nozzles
not working correctly at all frequencies, or even Gloss Enhancer (GE)
color problems.
b Inspector measuring tool test plot.
c Nozzle Print Test which is also part of the Image Quality Service Plot.
This test is designed to check that the Printhead nozzles print correctly.
The test prints out every single nozzle of each Printhead. No error hiding
or Printhead Alignment algorithm is applied. For each Printhead, you can
see both the adjacent and the consecutive nozzles.
This is what you would see in the Nozzle Print Test part if there are
nozzles not printing correctly:
1 On the right of each Printhead Nozzle test, there is a series of numbered
stepped diagonal lines. If one or more of the nozzles are malfunctioning or
mis-positioned, you will see that the stepped lines are broken or misdirected
in one or more places.
2 On the left of each Printhead Nozzle test, there is a series of horizontal
straight lines. If one or more nozzles are misdirected there will be unequal
spaces between the corresponding lines.
How to fix the Nozzle Defects
If the printer has nozzle defects, it does not mean that you will not get
perfect print quality results. The printer has automatic procedures to hide
many nozzle defects.
1 Recover the Printheads using the option through the Front Panel (Main
menu/Image quality maintenance/clean Printheads).
2 Reprint the Nozzle Print test to check that the defective nozzles have been
corrected.
3 If the problem continues, replace the faulty Printhead.
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HP Designjet Z3100/Z2100 GP Photo Printer Series — Service Manual
Print Quality
Advance Diagnostic: Force Drop Detection
If Nozzle Print Test plot has persistent white point banding in only one
color that cannot be fixed with a recovery you can use this option to resolve
the problem by resetting the nozzle health data base so that all nozzles are
assumed to be correct.
Once the nozzle health data base has been reset drop detection is forced.
The normal cause of this white point banding in a single color is the
incorrect detection of failed nozzles by the drop detector.
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Print Quality
Troubleshooting Print Quality Problems
Print Quality General Advice
1 To achieve the best performance from the printer, only genuine HP
accessories and supplies should be used.
2 Make sure that the paper type selected in the Front Panel is the same as
the paper type loaded into the Printer.
3 The most appropriate print quality settings for your purposes. A lower print
quality is likely to be seen if the print quality slider has been moved to the
Speed end of the scale, or the custom quality level set to Fast.
4 Check that the environmental conditions (temperature, humidity) are within
the temperature/humidity range as specified for the Printer (refer to the
User’s Guide for further information).
5 Check that the ink cartridges and printheads have not exceeded their
expiration dates.
Horizontal Lines Across the Image (Banding)
Description of problem
When you look at the image you have printed, there are horizontal lines
across the image. Shown below is an example of what you might see if you
have this problem:
Corrective Action
1 Check that the paper type loaded corresponds to the paper type selected in
the front panel and in the software.
2 Check that the appropriate print quality settings are being used and reprint
the image. In some cases print quality problems can be resolved by selecting
a higher print quality level.
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Print Quality
3 Print the Service Image Diagnostics Print, and clean any printheads that
need cleaning. Reprint the job in case the problem has been solved.
4 Check the paper advance calibration status. If the status is PENDING, y
perform the paper advance calibration. After calibration reprint the job.
Lines are Missing or Thinner than Expected
Description of problem
Shown below is an example of what you might see if you have this problem:
Corrective Action
1 Check that the paper type loaded corresponds to the paper type selected in
the front panel and in the software.
2 Check that the appropriate print quality settings are being used. Select the
custom print quality options in the Print dialog, and try turning on the
Maximum detail option. Reprint the job in case the problem has been
solved.
3 If the resolution of the image is greater than the printing resolution, a loss of
line quality may be seen. You can find the Max. Application Resolution
option in the Windows driver dialog's Advanced tab, under Document
Options > Printer Features. Reprint the job in case the problem has been
solved.
4 Check the Printhead alignment status. If the status is PENDING, perform the
paper advance calibration. After alignment reprint the job.
5 Check the paper advance calibration status. If the status is PENDING,
perform the paper advance calibration. After calibration reprint the job.
6 Using Part 3 of the Image Quality Diagnostic Print, check if there are a
significant amount of nozzles out in the color that is actually causing the
problem (if see you a problem with the Black color in the customer print, then
only check the Black printhead in the Image Quality Diagnostic Print). If
there is a significant amount of nozzles out then replace the faulty Printhead.
Problems with Stepped Lines
Description of problem
When you look at the image you have printed there are ‘stepped lines’ in
the borders of arrows and diagonal lines. The lines should be straight with
no stepping.
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Print Quality
Shown below is an example of what you might see if you have problems
with Stepped Lines:
Corrective Action
1 The problems may be inherent in the image that you are trying to print. Try
to improve the image with the application that generated the file.
2 Check that the appropriate print quality settings are being used.
3 Turn On the Maximum Detail option in the Driver.
4 Change the image rendering resolution to 300 dpi or 600 dpi depending
on the printing needs. You can find the Max. Application Resolution
option in the Windows driver dialog's Advanced tab, under Document
Options > Printer Features.
Lines are Printed Double or in Wrong Colors
Description of problem
This problem can have various visible symptoms, as shown below:
Colored lines are
printed double, in
different colors
Borders of colored
blocks are wrongly
colored
Corrective Action
1 Reseat the Printheads by removing them and then reinserting them.
2 Align the Printheads.
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HP Designjet Z3100/Z2100 GP Photo Printer Series — Service Manual
Print Quality
Lines are discontinuous
If the lines are broken in the following way:
1 Check that the appropriate print quality settings are being used.
2 Reseat the Printheads by removing them and then reinserting them.
3 Align the Printheads.
Lines are Blurred (Ink Bleeds from Lines)
Description of problem
This problem is often caused by the ink soaking into the paper, making the
lines blurred and fuzzy. This could be because of the humidity in the air.
Corrective Action
1 Check that the environmental conditions (temperature, humidity) are suitable
for high-quality printing.
2 Make sure that the paper type selected in the Front Panel is the same as
the paper type loaded into the Printer.
3 Try using a heavier paper type, such as HP Heavyweight Coated Paper, HP
Super Heavyweight Coated Paper, or Digital Fine Art paper.
4 If glossy paper is being used, try changing to a different type of glossy
paper.
5 Select the custom print quality options in the Print dialog, and turn on the
More passes option
6 Allow the prints time to dry separately; do NOT cover or stack them.
7 Align the printheads.
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Print Quality
Problems with Graininess
Description of problem
Shown below is an example of what you might see if you have problems
with graininess:
Corrective Action
1 Check that the paper type loaded corresponds to the paper type selected in
the front panel and in the software.
2 Check that printing is on the correct side of the paper.
3 Check that the appropriate print quality settings are being used. Select the
custom print quality options in the Print dialog, and try turning on the More
passes detail option. Reprint the job in case the problem has been solved.
4 Check the Printhead alignment status. If the status is PENDING, perform the
paper advance calibration. After alignment reprint the job.
5 Check the paper advance calibration status. If the status is PENDING,
perform the paper advance calibration. After calibration reprint the job.
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HP Designjet Z3100/Z2100 GP Photo Printer Series — Service Manual
Print Quality
Paper is not Flat
Description of problem
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.
Shown below is an example of what you might see if you have problems
with the paper not being flat:
Corrective Action
1 Check that the paper type loaded corresponds to the paper type selected in
the front panel and in the software.
2 Try using a heavier paper type. When printing dense colors, it is
recommended to use HP Heavyweight Coated Paper HP Super,
Heavyweight Coated Paper or thicker Digital Fine Art papers.
3 Make sure that only genuine HP paper is being used.
4 Check that the appropriate print quality settings are being used.
5 Check that the environmental conditions (temperature, humidity) are within
the temperature/humidity range as specified for the Printer (refer to the
User’s Guide for further information).
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Print Quality
Print Scuffing or Scratching when Touched
Description of problem
The black ink pigment can smudge when touched by a finger, a pen, or
some other object. This is particularly noticeable on coated paper, matte
proofing paper, and fine art material.
Glossy paper may be extremely sensitive to damage from the basket or to
anything else that it contacts soon after printing, depending on the amount
of ink used and the environmental conditions at the time of printing.
Corrective Action
1 Handle prints carefully.
2 Avoid stacking prints on top of each other.
3 Disable the automatic cutter before printing, so that the print will not fall into
the basket.
Ink marks on the paper
This problem may 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).
Corrective Action
1 Check that the paper type loaded corresponds to the paper type selected in
the front panel and in the software.
2 Use a recommended paper type and the correct print settings.
3 If using sheet paper, try rotating the sheet 90 degrees. The orientation of the
paper fibers may affect performance.
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Print Quality
4 Try changing to a thicker paper type, such as HP Heavyweight Coated
Paper, HP Super Heavyweight Coated Paper, or thicker Digital Fine Art
papers.
5 Try to increase the margins by relocating the image to the center of the page
with the software application being used.
Ink marks on the back of the paper
This can happen after a lot of border less printing, especially with nonstandard paper sizes. Ink residues on the platen are likely to mark the back
of the paper.
Corrective Action
„ Clean the platen with a soft cloth. Clean each rib separately without
touching the foam between the ribs.
Problems with the Edges of objects
Stepped or not sharp
The edges of objects or lines appear to be poorly defined or lighter in
density than expected.
Corrective Action
„ If the print quality slider has already been set to Quality in the Print
dialog, select the custom print quality options, and try setting the quality
level to Normal.
Darker than expected
The edges of objects seem darker than expected.
Corrective Action
„ If the print quality slider has already been set to Quality in the Print
dialog, select the custom print quality options, and try setting the quality
level to Normal.
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Print Quality
Bronzing
When printing on photo paper with gray and black ink only a gloss
differential problem can be encountered when light is directly reflected from
the print, producing 'bronzed' reflections where ink has been laid.
Corrective Action
„ Use the Full set of inks option.
Black and white prints do not look neutral
Consider using the Gray and Black inks only. See Print in gray shades.
Horizontal lines at the end of a cut sheet print
There is a type of defect that only affects the end of a print, within
approximately 30 mm of the trailing edge of the paper. Some very thin
horizontal lines may be seen across the print.
Corrective Action
1 Print the Service Image Diagnostics Print, and clean any printheads that
need cleaning. Reprint the job in case the problem has been solved.
2 Try printing with roll paper.
3 Try using larger margins around the image.
Vertical lines of different colors
The print has vertical bands of different colors along it.
Corrective Action
1 Use thicker paper, choosing from the recommended paper types such as HP
Heavyweight Coated Paper and HP Super Heavyweight Paper.
2 Use higher print quality settings.
White spots on the print
White spots are seen on the print. This is probably due to paper fibers, dust,
or loose coating material.
Corrective Action
1 Clean the paper manually with a brush before printing, to remove any loose
fibers or particles.
2 Always keep the cover of the printer closed.
3 Protect paper rolls and sheets by storing them in bags or boxes.
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Print Quality
Problems with Color Accuracy
Corrective Action
1 Ensure that the paper type being used has been color calibrated, which will
give color consistency from print to print, and from Printer to Printer.
2 Check that printing is on the correct side of the paper.
3 Check that the appropriate print quality settings are being used.
4 Select suitable options in the application (refer to the User’s Guide for more
information).
5 Print the Service Image Diagnostics Print, and clean any printheads that
need cleaning. Reprint the job in case the problem has been solved.
Color accuracy using EPS or PDF images in page layout
applications
Page layout applications such as Adobe InDesign and QuarkXPress do not
support color management of EPS, PDF, or grayscale files.
If these types of files have to be used, try to ensure that the EPS, PDF, or
grayscale images are already in the same color space that is intended to be
used later on in Adobe InDesign or QuarkXPress. For instance, if the final
objective is to print the job in a press that follows the SWOP standard, at the
time of creating the EPS, PDF or grayscale the image should be converted
into SWOP.
Output Only Contains a Partial Print
If the output that was expected only contains a partial image, then try the
following to resolve the problem:
1 Was the Cancel key pressed before all the data was received by the Printer?
If so, send the file again and make sure that the Cancel key is not pressed.
2 The I/O Timeout setting may be too short. Increase the I/O timeout setting
(Setup Menu/I/O Setup/IO Timeout) and then send the file again.
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Print Quality
3 There might be a communications problem between the Printer and
Computer. Check the USB or network cable between the computer and the
Printer to make sure it is not damaged and is connected correctly.
4 Make sure that the software settings are correct for the current page size
(e.g. long-axis prints).
5 If network software is being used, make sure it has not timed out.
Problems with Image Clipping
This normally indicates a discrepancy between the actual printable area on
the loaded paper and the printable area as understood by the software. This
kind of problem can often be identified before printing by previewing the
print.
„ Check the actual printable area for the paper size that is loaded.
printable area = paper size – margins
„ Check what the software understands to be the printable area (which it
may call “printing area” or “imageable area”). For example, some
software applications assume standard printable areas that are larger
than those used in this Printer.
„ If a custom page size with very narrow margins has been defined, the
printer may impose its own minimal margins, clipping the image slightly.
Consider using a larger paper size, or border less printing.
„ If the image contains its own margins, it may be possible to print it
successfully by using the Clip Contents by Margins option.
„ If a very long image needs to be printed on a roll, check that the software
is capable of printing an image of that size.
„ The page may have been rotated from portrait to landscape on a paper
size that is not wide enough.
„ If necessary, change the printable area in the software.
Another Possible Explanation
Some applications, such as Adobe Photoshop, Adobe Illustrator, and
CorelDRAW, use an internal 16–bit coordinate system which means that
they cannot handle an image of more than 32,768 pixels. If you try to print
an image larger than this from these applications, the bottom of the image
will be clipped. In this case, the only way to print the whole image is to
reduce the resolution so that the whole image requires fewer than 32,768
pixels. The HP-GL/2 printer driver contains an option called Compatibility
with 16–bit applications, which can be used to reduce the resolution of
such images automatically. This option can be found option in the Advanced
tab, under Document Options > Printer Features.
Some objects are missing from the printed image
Large quantities of data may be necessary to print a high-quality largeformat print job, and in some specific workflow there may be issues that can
lead to some objects missing from the output.
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Corrective Action
„ In the Advanced tab, select Document options, Printer features, and set
Send job as bitmap to Enabled (HP-GL/2 driver only).
„ In the Advanced tab, select Document options, Printer features, and set
16-bit App. Compatibility to Enabled.
„ In the Advanced tab, select Document options, Printer features, and set
Max. Application resolution to 300.
The above settings are mentioned for troubleshooting purposes and may
adversely affect the final output quality or the time necessary to generate the
print job. Therefore, they should be restored to their default values if they do
not help to solve the problem.
When working under Mac OS, the above settings are not available. Instead,
try reducing the resolution of bitmap images in the application software
being used.
A PDF file is clipped or objects are missing
In older versions of Adobe Acrobat or Adobe Reader, large PDF files could
be clipped or lose some objects when printing with the HP-GL/2 driver at
high resolution. Upgrade the Adobe Acrobat or Adobe Reader software to
the latest version. From version 7 onwards, these problems should be solved.
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