HP Designjet Z5200ps User Manual

							To control the output of color imaging devices, the following color spaces are normally used:
●RGB (Red, Green and Blue) is the color space typically used for additive devices. A color is
represented as a combination of specific quantities of red, green and blue colorants and all such
combinations address the range of colors (color gamut) of the chosen device.
NOTE:Subtractive devices can also be controlled using RGB data and, especially when you
do not require control over how you want to use your printer’s black ink, this is an efficient
option.
●CMYK (Cyan, Magenta, Yellow and Black) is the color space for subtractive devices, such as
printers or presses. A color is represented as a combination of cyan, magenta, yellow and black
(K) inks and all such combinations let you address the entire range of colors of the chosen
device.
Both of these color spaces are only ways of controlling different color imaging devices and their
values do not describe colors directly. The same CMYK values, for example, will give different colors
when sent to different printers that use different inks and paper types. For example, consider a printer
that can use indoor inks or outdoor inks. The printer (hardware) is the same, but it has two different
color gamuts due to the different chemistry of the inks (dye-based versus pigmented). Furthermore,
they need to work with different paper types, as ink interaction with the paper depends on its
chemistry. Thus, the colors resulting from given CMYK values depend on the types of inks and
papers that you use with a printer. If this is the case using the same printer, you can easily imagine
how different results can be obtained with printers using different technologies and therefore using
different ink chemistry.
The same happens with RGB-controlled devices. For example, imagine that two different monitors
from the same manufacturer have their white points at 9600 K and 6500 K respectively. Their colors
are going to be different because they will be related to a different white point reference. The situation
is even worse when comparing monitors from different manufacturers. As a recommendation, set the
white point of your monitor to 5000 K (also called D50), since this is the standard color temperature
for the graphic arts industries. If you dislike the appearance of D50 (you may find it too yellowish), the
second choice is to set the display to 6500 K (D65).
NOTE:The white point is the brightest neutral color that a device can reproduce or that is present in
an image. The human visual system automatically adapts to the content of an image with respect to
its white point.
Furthermore, an RGB image, such as an image obtained from a digital camera and edited on a
monitor, needs to be first converted to CMYK for a specific printer before printing. Unfortunately
different devices do not give access to the same color gamuts: there are some colors that can be
shown on a display that cannot be matched in print and vice versa. The following graphic illustrates
how colors visible to the human eye are greater than those reproduced by a typical display or printer
using a specific paper type and also how the color gamuts accessible using these two color imaging
devices do not match each other.
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							1.All colors
2.Computer monitor gamut
3.CMYK press gamut
Finally, there are some color spaces that are not device-dependent, but instead represent how a
viewer sees colors, such as CIE Lab or CIECAM02 defined by the CIE (Commission Internationale de
l’Éclairage). The advantage of these spaces is that, unlike CMYK or RGB, if two objects have the
same CIE Lab values then they will look the same when viewed under the same conditions. Values in
these spaces can be obtained from measuring the light emitted or reflected by an object.
The solution: color management
There are many colors from an RGB-controlled device that can no be reproduced in a CMYK-
controlled device and vice versa. These colors are called “out-of-gamut” colors. The industry uses two
steps to reduce color differences as much as possible:
●Describe the color behavior of each device as accurately as possible
●Convert one color gamut to another as effectively as possible
The solution:
1.Describe the color behavior of a device as accurately as possible using an ICC profile. By
taking various RGB or CMYK combinations, sending them to a device, measuring the resulting
output and expressing it in a device-independent color space (e.g. CIE Lab), the color behavior
of a device can be described. The resulting relationship is stored in an ICC profile, which is a
standard file that acts as a dictionary to translate the device’s color space (CMYK or RGB) to a
device-independent color space (e.g. CIE Lab). The process of generating an ICC profile is
called profiling.
2.Convert colors as effectively as possible using a Color Management System (CMS). A
CMS is software that uses information from ICC profiles to transform one device’s color space
(defined by a source profile) into the color space of another device (defined by a destination
profile). The difficult part of the job is with those colors that exist in one device’s gamut but not in
the other. We will explore this in more detail later on.
Briefly, we can describe any CMS by the following 4 settings:
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							●CMS: CMS stands for Color Management System. It is the application that converts the color
information stored in the input image, which has the color space defined by a source profile, into
an output image that has the color space specified by a destination profile. There are many
different CMSs on the market: there are CMSs in applications, in operating systems and in
printing software provided by printer manufacturers (in our case the HP Designjet Z5200ps
internal RIP).
●Source profile: a description of the color behavior of the input device.
●Destination profile: a description of the color behavior of the output device.
●Rendering intent: the most difficult challenge in color management is when a color in the
source gamut does not correspond directly to a color in the destination gamut. As a perfect
match is not possible, there are different types of choices that can be made about how to treat
gamut differences and these are called rendering intent. There are four different possibilities
depending on the final output you want to achieve.
◦Use Perceptual for the most pleasing final output from your original RGB image. It is
suitable for photographic content.
◦Use Saturation for vivid final output. It is suitable for business graphics (charts,
presentations, etc.), but is not recommended for color matching.
◦Use Relative Colorimetric for press proofing. This rendering intent provides a match for
colors that are inside both the source and destination gamuts and minimizes differences
when a match is not possible.
◦Use Absolute Colorimetric for press proofing (like Relative Colorimetric), when you also
want to simulate the color of the source’s paper.
TIP:You can use soft proofing options in your application (such as Photoshop and InDesign) to
view the result of each rendering intent. See 
Proof the output on the monitor (InDesign, PS driver)
on page 91.
The most commonly used device color spaces and, therefore, profiles are:
●RGB mode:
◦sRGB (sRGB IEC61966-2.1): for images originating typically from consumer digital
cameras and scanners and in general from the Web
◦Adobe RGB (1998): for images originating typically from professional digital cameras
◦Specific RGB device space: for images coming from or going to a specific RGB device
that has been profiled. The HP Designjet Z5200ps has the capability to measure itself and
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							generate an RGB ICC profile, describing its color behavior for the paper that was loaded at
the time of measuring.
●CMYK mode:
◦SWOP: abbreviation of “Specifications for Web Offset Publications”, a set of press
standards defined for a typical US press and for different types of paper
◦ISO 12647-2: a set of press standards defined by the International Standards Organization
for different types of paper (Coated, Uncoated, …)
◦Other regional standards: Euroscale, JMPA, Japan Color
◦Specific CMYK device space: for images coming from or going to a specific CMYK device
that has been profiled
Color and your printer
As a creative professional, predictable and dependable results from your printer are essential to
getting your job done. Predictability is a key element of an efficient color workflow. You need prints
that match your expectations with neutral grays and correct colors on your selected paper. Your prints
should be produced consistently print-to-print and printer-to-printer. Dependability ensures that every
print is free of print-quality defects and ready to use or send to your customer. You save time and
effort and avoid wasting ink and paper, and you can meet demanding production schedules by
printing overnight with confidence.
HP Designjet Z5200ps printers have been engineered with advanced hardware and driver features to
ensure predictable and dependable results, and offer dramatic improvements in efficiency and control
for your color workflow.
HP Embedded Spectrophotometer
HP Designjet Z5200ps printers revolutionize professional color workflows by using a built-in
spectrophotometer for color calibration and profiling.
A spectrophotometer is a precision instrument that can determine the exact composition of light
reflected from a color patch. It splits the reflected light into different wavelength components, just as
Newton’s prism splits white light into the colors of the rainbow, and measures the strength of each
component. The HP Embedded Spectrophotometer is mounted on the printhead carriage.
The spectrophotometer allows HP Designjet Z5200ps printers to generate custom ICC profiles
automatically for your preferred paper types and calibrate the printers to deliver print-to-print and
printer-to-printer repeatability with less than half the color error of earlier HP Designjets, under all
environmental conditions, and even on unknown (not factory-profiled) paper types. A built-in white
calibration tile, protected by an automatic shutter, ensures reliable measurements that meet
international standards.
The printer, color imaging pipeline and professional-quality spectrophotometer with GretagMacbeth i1
color technology are integrated with the HP Color Center software for the HP Designjet Z5200ps.
Giving the calibration and profiling processes direct access to the writing system allows precise
control of ink levels and color separations for each printed color patch. The automated measurement
process eliminates handling the test print, provides repeatable drying times, and allows fast
measurements with precise electromechanical positioning of the spectrophotometer over the color
patch. This provides unprecedented ease of use and matches or exceeds the performance of more
expensive off-line, handheld profiling systems.
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							A summary of the color management process
To get the accurate and consistent colors that you want, you should follow these steps for each paper
type that you use.
1.If your paper type is not already known to the printer, add it to the printers list of known papers.
See 
To create your own paper preset on page 37. Typical users may add a few custom paper
types every year.
2.Color-calibrate the paper type, for consistent colors. Calibration should be repeated every now
and then, when recommended by a printer alert (typically, every few weeks for each paper type
you use). In addition, you may wish to calibrate immediately before a particularly important print
job for which color consistency is vital.
3.Color-profile the paper type, for accurate colors. Profiling does not normally need to be repeated:
once you have a profile for a particular paper type, you can continue to use it. However, re-
profiling does no harm, and some users repeat the profiling process every month to ensure that
the profile is up to date.
4.When printing, select the correct color profile for the paper type you are using.
If you use a paper type already defined in the printer, it has a color profile already, but you should at
least calibrate it before using it.
If you define a new paper type, you are automatically led through the steps of calibration and profiling.
The following diagram shows the operations handled by the HP Color Center, in the correct order.
NOTE:You can perform all three operations in sequence as shown, but you can also choose to
start with or stop after any of the three operations. With one exception: color calibration is performed
automatically after adding a new paper type.
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							Color calibration
Color calibration enables your printer to produce consistent colors with the particular printheads, inks
and paper type that you are using, and under your particular environmental conditions. After color
calibration, you can expect to get identical prints from any two different printers situated in different
geographical locations.
Calibration should be done in any of the following circumstances:
●Whenever a printhead is replaced
●Whenever a new paper type is introduced that has not yet been calibrated with the current set of
printheads
●Whenever a certain amount of printing has been done since the last calibration
●Whenever the printer has been turned off for a long period of time
●Whenever the environmental conditions (temperature and humidity) change significantly
The printer driver usually reminds you with an alert whenever you need to perform color calibration,
unless you have disabled the alerts. However, there will be no alert if the environmental conditions
change.
You should calibrate a paper type before creating its color profile; however, you can later recalibrate
without needing to recreate the color profile.
You can turn off color calibration from the front panel: select the Image Quality Maintenance menu
icon 
, then set Enable color calibration to OFF. In this case, the printer will use a default
calibration set in the factory for all paper types. If you later turn color calibration back on, it will still
remember any calibrations that you performed earlier.
Check calibration status
You can check the color calibration status of the currently loaded paper at any time by pressing the
View loaded paper key on the front panel. The status may be one of the following:
●PENDING: the paper has not been calibrated.
NOTE:Whenever you update the printers firmware, the color calibration status of all papers is
reset to PENDING. See 
Update the firmware on page 121.
●OBSOLETE: the paper has been calibrated, but the calibration is now out of date for one of the
reasons mentioned above, and should be repeated.
●OK: the paper has been calibrated, and the calibration is up to date.
●N/A: this paper cannot be calibrated. The following paper types cannot be calibrated: plain
paper, transparent materials, and textured glossy paper (such as HP Collector Satin Canvas).
They can, however, be profiled.
Calibrate
You can start color calibration in the following ways:
●From the printer driver alert that recommends calibration.
●From the HP Color Center: select Paper Preset Management > Calibrate Paper.
●
From the front panel: select the Image Quality Maintenance menu icon 
, then Calibrate
color.
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							The calibration process is fully automatic and can be performed unattended after you have loaded
paper of the type you wish to calibrate—which should be A4, Letter or any larger size.
The process takes about 8–10 minutes and consists of the following steps.
1.A calibration test chart is printed, which contains patches of each ink used in your printer.
2.The chart is allowed to dry for a period of time that depends on the paper type, so that the colors
have time to stabilize.
3.The chart is scanned and measured using the HP Embedded Spectrophotometer.
4.From the measurements made by the spectrophotometer, the printer calculates the necessary
correction factors to apply for consistent color printing on that paper type. It also calculates the
maximum amount of each ink that can be applied to the paper.
TIP:If color calibration fails, check whether a color is missing from the chart. A missing color may
be caused by a printhead problem: see 
Troubleshooting ink cartridge and printhead issues
on page 158.
NOTE:Matte black is not used on glossy or satin papers, so that column of the chart is not printed
when calibrating those paper types.
Calibration from Photoshop
When you use Adobe Photoshop CS3 (or later version) for Windows, the Print window can warn you
if the paper needs color calibration, and can provide an icon 
 to launch the HP Utility to perform the
calibration.
To enable this capability under Windows XP, you must download and install the following free
software packages from Microsofts Web site:
●Microsoft Core XML Services (MSXML) 6.0
●Microsoft XML Paper Specification Essentials Pack 1.0
Color profiling
Color calibration provides consistent colors, but consistent colors are not necessarily accurate. For
instance, if your printer prints all colors as black, its colors may be consistent but they are not
accurate.
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							In order to print accurate colors, it is necessary to convert the color values in your files to the color
values that will produce the correct colors from your printer, your inks and your paper. An ICC color
profile is a description of a printer, ink and paper combination that contains all the information needed
for these color conversions.
When you have defined and calibrated a new paper type, the printer is ready to create a ICC profile
for use with your paper, which will allow you to print on it with the best possible color accuracy.
Alternatively, if your paper type is already known to the printer, you already have an appropriate ICC
profile for use with it.
Create your own profile
You can create a color profile easily by using the HP Color Center: select Paper Preset
Management > Profile Paper. The printer helps you by prompting for information about the paper,
then creates and installs the new profile automatically.
The process takes about 15–20 minutes and consists of the following steps.
1.A profiling chart is printed, which contains patches of each ink used in your printer. Unlike a
calibration chart, most of the patches contain combinations of more than one ink.
The printer chooses automatically between two profile charts:
●An A3 or B format for cut sheets
●A roll-paper format that minimizes paper use by printing across the full width of the roll
2.The chart is allowed to dry for a period of time that depends on the paper type, so that the colors
have time to stabilize.
NOTE:If you would like to use a longer drying time, you can ask the HP Color Center to create
the chart without going on to create a profile (Windows: Print target only; Mac OS: Print ICC
profiling chart). Then, later, when the chart is completely dry, you can restart the HP Color
Center and ask it to create a profile using the chart you have already created (Windows: Create
ICC profile from a target that has already been printed; Mac OS: Scan ICC profiling chart
and create ICC profile). In this case the spectrophotometer takes a while to warm up before it is
ready to scan.
3.The chart is scanned and measured using the HP Embedded Spectrophotometer.
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							NOTE:Chart measurement may not be successful if you load the chart as a single sheet with
skew checking disabled.
4.From the measurements made by the spectrophotometer, the printer calculates the ICC profile
for your printer, inks and paper type.
5.The new ICC profile is stored in the correct system folder on your computer, where your
application programs can find it.
The profile is also stored in the printer, so that other computers connected to the same printer
can copy it. The HP Utility will notify you if your printer has profiles that are not yet stored on
your computer.
NOTE:Some applications may need to be closed and restarted in order to use a profile that has just
been created.
Profile your monitor
You are also recommended to calibrate and profile your monitor (display device), so that the colors
you see on the screen are more closely related to those you see on your prints. From the HP Color
Center, select How To Calibrate Your Display for further information.
Color management options
The aim of color management is to reproduce colors as accurately as possible on all devices: so that,
when you print an image, you see very similar colors as when you view the same image on your
monitor.
There are two basic approaches to color management for your printer:
●Application-Managed Colors: in this case your application program must convert the colors of
your image to the color space of your printer and paper type, using the ICC profile embedded in
the image and the ICC profile of your printer and paper type.
●Printer-Managed Colors: in this case your application program sends your image to the printer
without any color conversion, and the printer converts the colors to its own color space. The
details of this process depend on the graphics language that you are using.
◦PostScript: the PostScript interpreter module inside the printer performs the color
conversion using the profiles stored in the printer (including those generated by the HP
Color Center) and any additional profiles sent with the PostScript job. This kind of color
management is done when you are using the PostScript driver and you specify printer color
management or when you send a PostScript, PDF, TIFF or JPEG file directly to the printer
through the Embedded Web Server. In either case you have to select the profiles to use as
default (in case the job doesnt specify any) and the rendering intent to apply.
◦Non-PostScript (PCL3): the color management is done using a set of stored ICC profiles.
This method is somewhat less versatile than the previous methods, but is a little simpler
and faster, and can produce good results with standard HP paper types. This kind of color
management is done when you are using a non-PostScript driver and you specify printer
color management, or when you send a PCL3 file directly to the printer through the
Embedded Web Server.
There are only two color spaces that the printer can convert to its own color space using
the stored profiles: Adobe RGB and sRGB if you are using Windows, Adobe RGB if you are
using Mac OS. In addition, you can use ColorSync.
ColorSync is the Mac OS built-in Color Management System; so, when you select
ColorSync, color management is performed by Mac OS, and it is done based on the ICC
profiles of the specified paper type. ColorSync is available with the PCL3 driver only.
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							ColorSync can be selected under Mac OS X 10.4 from the Color Options panel, then
select Use Embedded (ICC/ColorSync) from the Source Profile drop-down list. Under
Mac OS X 10.5 and 10.6, ColorSync can be selected from the Color Matching panel.
You are recommended to consult the Knowledge Center at 
http://www.hp.com/go/Z5200ps/
knowledgecenter/ to see how to use the color management options of your particular application.
To choose between Application-Managed Colors and Printer-Managed Colors:
●In the Windows driver dialog: select the Color tab.
●In the Mac OS Print dialog: select the Color Options panel.
●In some applications: you can make this choice in the application.
Color management example with Photoshop
In this example, you have an Adobe RGB image that you want to print from Photoshop. There are
three ways of doing it.
●Select Let Photoshop determine colors in Photoshop. Select Application-Managed Colors in
the printer driver. Color management is done in Photoshop. This is the recommended way.
●Select Let printer determine colors in Photoshop. Select Printer-Managed Colors and the
sRGB profile in the printer driver. Photoshop converts the image from Adobe RGB to sRGB and
sends it to the printer. Color management is done in the printer. Unfortunately, conversion to
sRGB results in a loss of gamut, but Photoshop cannot be prevented from converting to sRGB
when Let printer determine colors is selected.
●Select No color management in Photoshop. Select Printer-Managed Colors and the
AdobeRGB profile in the printer driver. Photoshop does not perform any conversion, there is no
loss of gamut, and color management is done in the printer. However, this method will not work
if you are using synchronized color management in Photoshop (see below).
Synchronized color management with Photoshop
If you are using Adobe Photoshop CS2 for Mac OS, or Adobe Photoshop CS3 for Windows, or later
versions, the color management options can be automatically synchronized between Photoshop and
the driver.
●If you select Let Photoshop determine colors or No color management in Photoshop,
Application-Managed Colors is automatically selected in the driver.
●If you select Let printer determine colors in Photoshop, Printer-Managed Colors is
automatically selected in the driver. The PostScript driver will use the color profile attached to
the job by Photoshop.
To enable this Photoshop synchronization under Windows XP, you must download and install the
following free software packages from Microsofts Web site:
●Microsoft Core XML Services (MSXML) 6.0
●Microsoft XML Paper Specification Essentials Pack 1.0
Perform black point compensation
NOTE:This option is available only when printing a PostScript or PDF job.
The black point compensation option controls whether to adjust for differences in black points when
converting colors between color spaces. When this option is selected, the full dynamic range of the
source space is mapped into the full dynamic range of the destination space. It can be very useful in
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