HP Designjet T1200 User Manual

							5.If you are using glossy paper, try changing to a different type of glossy paper.
6.Align the printheads. See 
Align the printheads on page 168.
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 184.
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 accuracy.
2.Set the Print Quality slider to Quality.
3.Maintain the room at a steady temperature between 10 and 30°C (50 and 86°F).
4.Load the roll of film and let it rest for five minutes before printing.
5.If you are still not satisfied, try recalibrating the paper advance. See 
Recalibrate the paper
advance on page 145.
The whole image is blurry or grainy
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 information key 
.
2.Check that you are printing on the correct side of the paper.
3.Check that you are using appropriate print-quality settings (see 
Printing on page 49). In some
cases, you can overcome a print-quality problem merely by selecting a higher print-quality level.
For instance, if you have set the Print Quality slider to Speed, try setting it to Quality. If you
change the print-quality settings, you may wish to reprint your job at this point in case the
problem has been solved.
4.
Go to the front panel and select the Ink menu icon 
, then Printhead information to see the
printhead alignment status. If the status is PENDING, you should align the printheads. See 
Align
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							the printheads on page 168. After alignment, you may wish to reprint your job in case the
problem has been solved.
5.
Go to the front panel and press the View information key 
 to see the paper advance calibration
status. If the status is DEFAULT, you should perform paper advance calibration: see 
Recalibrate
the paper advance on page 145.
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 software. To check on the front panel, use the View information key 
.
2.Try changing to a thicker paper type, such as HP Heavyweight Coated Paper or HP Super
Heavyweight Plus Matte Paper.
3.Select a paper type that is slightly thinner than the paper you have loaded; this will persuade the
printer to use less ink. Here are some example paper types in ascending order of thickness:
Plain Paper, Coated Paper, Heavyweight Coated Paper, Super Heavyweight Plus Matte Paper.
The print is scuffed or scratched
The black ink pigment can be scuffed or scratched when touched by a finger, a pen or some other
object. This is particularly noticeable on coated paper.
Glossy paper may be extremely sensitive to 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.
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							To reduce the risk of scuffs and scratches:
●Handle prints carefully.
●Avoid stacking prints on top of each other.
●Catch your prints as they are cut from the roll and do not let them fall into the basket.
Alternatively, leave a sheet of paper in the basket so that freshly printed sheets do not make
direct contact with the basket.
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 key and
also cancel the job from your computer application. Soaked paper can damage the printheads.
Try the following suggestions to avoid this problem:
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 information key 
.
2.Use a recommended paper type (see 
Order paper on page 129) 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.
4.Try changing to a thicker paper type, such as HP Heavyweight Coated Paper and HP Super
Heavyweight Plus Matte Paper.
5.Select a paper type that is slightly thinner than the paper you have loaded; this will persuade the
printer to use less ink. Here are some example paper types in ascending order of thickness:
Plain Paper, Coated Paper, Heavyweight Coated Paper, Super Heavyweight Plus Matte Paper.
6.Try to increase the margins by relocating the image to the center of the page using your
software application.
Ink marks on the back of the paper
This can happen after a lot of borderless printing, especially with non-standard paper sizes. Ink
residues on the platen are likely to mark the back of the paper.
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							Clean the platen with a soft cloth. Clean each rib separately without touching the foam between the
ribs.
Black ink comes off when you touch the print
This problem may be caused by printing with matte black ink on glossy paper. The printer will not use
matte black ink if it knows that the paper will not retain it. To be sure of avoiding matte black ink, you
can select Photo Glossy Paper as the paper type (in the Photo Paper category).
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, select the custom print-quality options, and try
setting the quality level to Normal. See 
Printing on page 49.
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, select the custom print-quality options, and try setting the quality level to
Normal. See 
Printing on page 49.
Horizontal lines at the end of a cut sheet print
This type of defect affects only the end of a print, within approximately 30 mm of the trailing edge of
the paper. You may see some very thin horizontal lines across the print.
To avoid this problem:
1.Print the Image Diagnostics Print. See 
The Image Diagnostics Print on page 160.
2.Consider printing with roll paper.
3.Consider using larger margins around your image.
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							Vertical lines of different colors
If your print has vertical bands of different colors along it:
1.Try using thicker paper, choosing from the recommended paper types such as HP Heavyweight
Coated Paper and HP Super Heavyweight Paper. See 
Order paper on page 129.
2.Try using higher print-quality settings (see 
Printing on page 49). For instance, if you have set the
Print Quality slider to Speed, try setting it to Quality.
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 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 information key 
. At the
same time, check the color calibration status. If the status is PENDING or OBSOLETE, you
should perform color calibration: see 
Color calibration on page 66. If you have made any
changes, you may wish to reprint your job in case the problem has been solved.
2.Check that you are printing on the correct side of the paper.
3.Check that you are using appropriate print-quality settings (see 
Printing on page 49). If you have
selected the Speed or Fast options, you may not get the most accurate colors. If you change the
print-quality settings, you may wish to reprint your job at this point in case the problem has been
solved.
4.If you are using Application Color Management, check that the color profile you are using
corresponds to the selected paper type and print-quality settings. If you have doubts about which
color settings to use, see 
Color management on page 65.
5.If the problem consists of color differences between your print and your monitor, please follow
the instructions in the “How to calibrate your monitor” section of the HP Color Center. At this
point, you may wish to reprint your job in case the problem has been solved.
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							6.Print the Image Diagnostics Print. See The Image Diagnostics Print on page 160.
7.Try using the color adjustment options to produce the colors you want. See 
Color adjustment
options on page 69.
If the problem persists despite all the above actions, contact your customer service representative for
further support.
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 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, convert the image into
SWOP when you create it.
Colors are fading
If you print on instant-dry photo paper, your prints will fade rapidly. If you plan to display the prints for
more than two weeks, you should laminate them to achieve longer life.
Prints on swellable coated papers will fade much less rapidly. However, lamination will increase the
life of prints (depending on the type of lamination) with all paper types. For more information, consult
your laminate provider.
The image is incomplete (clipped at the bottom)
●Did you press Cancel before all the data were received by the printer? If so, you have ended the
data transmission and will have to print the page again.
●The I/O timeout setting may be too short. This setting determines how long the printer waits for
the computer to send more data, before deciding that the job is finished. From the front panel,
increase the I/O timeout setting to a longer period and then send the print again. From the
Connectivity menu 
, select Advanced > Select I/O timeout.
●There may be a communications problem between your computer and the printer. Check your
USB or network cable.
●Check to make sure that your software settings are correct for your current page size (for
example, long-axis prints).
●If you are using network software, make sure it has not timed out.
The image is clipped
Clipping normally indicates a discrepancy between the actual printable area on the loaded paper and
the printable area as understood by your software. You can often identify this kind of problem before
printing by previewing your print (see 
Preview a print on page 56).
●Check the actual printable area for the paper size you have loaded.
printable area = paper size – margins
●Check what your 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.
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							●If you have defined a custom page size with very narrow margins, the printer may impose its
own minimal margins, clipping your image slightly. You may want to consider using a larger
paper size, or borderless printing (see 
Select margins options on page 52).
●If your image contains its own margins, you may be able to print it successfully by using the Clip
Contents by Margins option (see 
Select margins options on page 52).
●If you are trying to print a very long image on a roll, check that your software is capable of
printing an image of that size.
●You may have asked to rotate the page from portrait to landscape on a paper size that is not
wide enough.
●If necessary, reduce the size of the image or document in your software application, so it fits
between the margins.
There is another possible explanation for a clipped image. 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.
NOTE:An image 32,768 pixels long would print at a length of 1.39 m (54.61 in) if you select Best or
Quality in the driver, 2.78 m (109.23 in) if you select Fast, Normal or Speed in the driver.
If you try to print an image larger than this from these applications, the bottom of the image may be
clipped. To print the whole image, try these suggestions:
●Try using the PostScript printer driver to print your job, if you have not already tried it.
●The Windows HP-GL/2 and HP RTL driver dialog includes an option called Max. application
resolution, which enables you to print successfully in this situation. You will not normally need
to change the default setting, which is Auto. However, you can find the option in the Advanced
tab, under Document Options > Printer Features.
●Save the file in another format, such as TIFF or EPS, and open it with another application.
●Use a RIP to print the file.
Some objects are missing from the printed image
Large quantities of data may be necessary to print a high-quality large-format print job, and in some
specific workflows there may be issues that can lead to some objects missing from the output. Here
are some suggestions to help you to avoid this problem.
●Try using the PostScript printer driver to print your job, if you have not already tried it.
●Select a smaller page size and scale to the desired final page size in the driver or in the front
panel.
●Save the file in another format, such as TIFF or EPS, and open it with another application.
●Use a RIP to print the file.
●Reduce the resolution of bitmap images in your application software.
●Select a lower print quality in order to reduce the resolution of the printed image.
NOTE:If you are working under Mac OS, not all of these options are available.
These options are suggested for troubleshooting purposes and may adversely affect the final output
quality or the time necessary to generate the print job. Therefore, they should be cancelled if they do
not help to solve the problem.
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							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 and HP RTL driver at high resolution. In order to avoid such
problems, upgrade your Adobe Acrobat or Adobe Reader software to the latest version. From version
7 onwards, these problems should be solved.
The Image Diagnostics Print
The Image Diagnostics Print consists of patterns designed to highlight printhead reliability problems.
It helps you to check the performance of the printheads that are currently installed in your printer, and
whether any printhead suffers from clogging or other problems.
To print the Image Diagnostics Print:
1.Use the same paper type that you were using when you detected a problem.
2.
Use the View information key 
 on the front panel to check that the selected paper type is the
same as the paper type loaded into the printer.
3.
At the printers front panel, select the Image Quality Maintenance menu icon 
, then Print
diagnostic image.
It takes about two minutes to print the Image Diagnostics Print.
The print is divided into two parts, both of which test printhead performance.
●Part 1 (top) consists of rectangles of pure colors, one for each printhead. This part represents
the print quality that you will get from each color.
●Part 2 (bottom) consists of small dashes, one for each nozzle on each printhead. This part
complements the first, and aims more specifically to detect how many faulty nozzles each
printhead has.
Please look carefully at the print. The names of the colors are shown above the rectangles and in the
center of the patterns of dashes.
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							First look at the upper part of the print (part 1). Each colored rectangle should be a uniform color
without any horizontal lines across it.
Then look at the bottom part of the print (part 2). For each individual colored pattern, check that most
of the dashes are present.
If you see horizontal lines in part 1 and also missing dashes in part 2 for the same color, the printhead
responsible needs cleaning. However, if the rectangles look solid, do not worry about just a few
missing dashes in part 2; these are acceptable because the printer can compensate for a few clogged
nozzles.
Here is an example of a gray printhead in a good state:
And here is an example of the same printhead in a bad state:
Corrective action
1.Clean any faulty printheads (see Clean the printheads on page 165). Then reprint the Image
Diagnostics Print to see whether the problem has been solved.
2.If the problem remains, clean the printheads again, and reprint the Image Diagnostics Print to
see whether the problem has been solved.
3.If the problem remains, consider cleaning your printheads manually (see 
Clean the printheads
on page 165). You could also try reprinting your current print job, in case it now prints
satisfactorily.
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							4.If the problem remains, try cleaning the printhead drop detector. The printer normally notifies you
when this is necessary, but it may be worth trying even if the printer has not suggested it. See
Clean the printhead drop detector on page 165.
5.If the problem still remains, replace any persistently faulty printheads (see 
Handling ink
cartridges and printheads on page 112), or contact HP Support (see Contact HP Support
on page 182).
If you still have a problem
If you still experience print-quality problems after applying the advice in this chapter, here are some
further things that you can do:
●Try using a higher print-quality option. See 
Printing on page 49.
●Check the driver you are using to print with. If it is a non-HP driver, consult the driver vendor
about the problem. You could also try using the correct HP driver, if feasible. The latest HP
drivers can be downloaded from 
http://www.hp.com/go/T770/drivers/ or http://www.hp.com/go/
T1200/drivers/.
●If you are using a non-HP RIP, its settings may be incorrect. See the documentation that came
with the RIP.
●Check that your printers firmware is up to date. See 
Update the firmware on page 125.
●Check that you have the right settings in your software application.
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