HP Scitex FB700 User Manual

							7 Calibrate the printer
When to calibrate
When to run Calibration Function
When loading a new media (but not
when loading a new roll or sheet of the
same media)Linearization (see RIP documentation
for instructions).Linearization of colors for accurate color
matching.
Horizontal Banding Media Feed Calibrates the media advance.
Poor output quality (apparent
misregistration of colors, banding)Auto Calibrations Calibrates the position of ink droplets in
relationship to each other and corrects
for individual jets not operating properly.
You can also run the Manual
Calibrations if necessary.
When printheads have been moved or
replaced (by an authorized service
provider)Auto Bidirectional or Manual
Bidirectional, and Head-to-HeadHead calibrations. Run Manual when
calibrating transparent or other media
that the onboard digital image sensor
cannot calibrate.
If Auto Calibrations do not improve print
quality, or if printing on transparent or
other media that cannot be detected by
the printerManual Calibrations Aligns printheads, allows you to map
out specific inkjets. Not normally
needed except when printing on
“invisible” media.
AutoJet
AutoJet detects individual inkjets that are misfiring or not firing at all. During subsequent printing, the
printer compensates for these jets by using other jets in their place, ensuring maximum print quality
without reducing print speed.
You can also identify and map missing jets manually from the Manual Calibrations menu (see 
Manual
Jet Mapping on page 50). You may want to manually map weak or misdirected jets that AutoJet
does not detect and substitute.
Jet replacement is not available in Express mode.
To run AutoJet:
●Select AutoJet Calibration from the Auto Calibrations menu (see 
Auto calibrations on page 46),
or
TIP:AutoJet does not work with transparent media, nor with many translucent media. In this case,
run Manual Jet Mapping, or map jets on opaque media before loading transparent/translucent media
for printing.
1.Press Calibrate from the Printing page, then press Auto Calibrations > AutoJet Calibration in
the menu.
2.The printer prints the AutoJet test pattern.
3.The printer reads the AutoJet test pattern and maps any missing jets to available working jets.
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							The control panel shows the progress of this operation as the percentage completed.
4.The printer prints an AutoJet report.
NOTE:The AutoJet calibration requires that the printheads are in correct alignment. If AutoJet
maps out a large number of jets even though there are no obvious jetting problems, the printhead Y
calibration (a factory calibration) may need to be performed again. In this case, contact HP or your
authorized service provider.
Auto calibrations
The printer’s piezo printheads are aligned by the installer. Head and bidirectional calibrations should
be necessary only rarely (for example, when the heads have been moved within the carriage or
replaced).
1.Press Calibrate from the Printing page, then press Auto Calibrations in the menu.
2.Select one of the Auto Calibrations.
●AutoBiDi (bidirectional) Calibration — ensures that every working jet fires at precisely the
same location (regardless of the carriage direction of travel).
●Auto Head X (head-to-head) Calibration — ensures that the printheads are in alignment
relative to each other.
●AutoJet Calibration — locates and substitutes missing jets for working jets (see 
AutoJet
on page 45).
●Full AutoSet — runs all three calibrations in sequence. The printer prints a test pattern then
reads it and makes the necessary adjustments or jet substitutions. After completing the
calibrations, a report is printed that shows:
◦Calibration results — a summary such as SUCCESSFUL CALIBRATION or an error
message
◦Header showing the date and time, software version, and printer type
◦Calibration detail — the calibration data for each head. The AutoJet detail reports how
many jets were mapped out by AutoJet, how many are permanently mapped out by
the operator, and whether the head is usable (from a jetout standpoint) in the various
print modes. The higher quality modes use jet replacement, so they can print
successfully with a greater number of jets out than Billboard mode.
●AutoSet Summary — when enabled, a table of the results of the Full AutoSet calibration is
printed after the AutoSet test patterns. When you enable the AutoSet Summary, you can
show or hide the detailed calibration data.
Manual calibrations
When you run the calibrations from this menu, you evaluate the calibration test patterns visually and
enter the calibration values via the control panel.
▲Press Calibrate from the Printing page, then press Manual Calibrations in the menu.
The Manual Calibration menu consists of these options:
●Media Feed Calibration — calibrates the media advance accuracy for band-free printing.
Visual and (for rigid media only) camera-assisted calibrations are available.
●Manual BiDi Registration — the manual version of AutoBiDi Calibration.
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							●Printhead X Calibration — the manual version of Auto Head X Calibration.
●Manual Jet Mapping — the manual version of AutoJet.
●Default Registration Data — sets all registration data to zero.
After calibration and jet mapping, perform a linearization or color calibration (as supported by the
RIP). See 
Linearization on page 53.
NOTE:The manual BiDi and X head calibrations are time-consuming and can be error-prone, but is
necessary when calibrating transparent media or other media that the printer’s digital image sensor
cannot calibrate.
Media Feed Calibration
This calibration allows you to calibrate the accuracy of the media advance. Inaccurate media advance
can result in blank spaces between print swaths (too much advance) or overlapping swaths (too little
advance).
1.On the Manual Calibrations menu, press Media Feed.
2.Press the Yes button to proceed. The control panel displays the following options:
990 mm (39 in) calibration — sheet fed only, uses the printers onboard image sensor for precise
adjustments. If the media feed needs larger adjustments, use the ruler-measured calibrations
first. Use for maximum accuracy.
510 mm (20 in) calibration — sheet fed only, uses the printers onboard image sensor for precise
adjustments. If the media feed needs larger adjustments, use the ruler-measured calibrations
first. Use to conserve media.
900 mm (34 in) calibration — prints a 900 mm (34 in) test pattern so you can verify its length
with an accurate metal ruler. Cut the pattern from the media web, then measure and adjust the
media advance as needed until the pattern is exactly 900 mm (34 in) long.
250 mm (10 in) calibration — prints a 250 mm (10 in) test pattern so you can verify its length
with an accurate metal ruler. This is not as precise as the 900 mm (34 in) calibration, but it uses
less media. Measure and adjust the media advance as needed until the pattern is exactly 250
mm (10 in) long.
The image-sensor based calibration (sheet-fed media only) prints a reference pattern, ejects the
media, and prompts you to rotate and reload the media so the pattern can be measured. To
account for the slight variability in the media feed mechanism, repeat these calibrations three to
five times to obtain the best calibration. The software allows you to position the patterns
anywhere on the sheet so you can print multiple iterations on the same sheet.
Input MFN — enter the Media Feed Number that was displayed after a previous media feed
calibration, to return to that setting without performing the calibration again.
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							TIP:To achieve the best results from the ruler-measurement calibrations: Use a good-quality
ruler with accurate marks. Use a ruler that is in the same units as the pattern selected. (Do not
attempt to use a metric ruler to read an English-units pattern or vice-versa.) Use a ruler that is at
least as long as the pattern you are measuring. (Do not attempt to add up shorter ruler
measurements to achieve the total length of the pattern.)
To avoid ruler issues, use the image-sensor based calibration.
Figure 7-1  Media feed calibration pattern
Manual BiDi Registration
Bidirectional registration is a method to align each of the printheads so that dot placement is accurate
in both directions along the X axis (along the direction of printhead travel).
The bidirectional registration pattern consists of a series of vertical lines. Half the pixels in this pattern
are printed in one direction, half of them in the other direction. When the pixels are accurately aligned,
the pattern is clear. When the dots are not aligned, the pattern appears fuzzy and ill-defined.
NOTE:AutoBiDi Calibration is the automatic version of this calibration. Try AutoBiDi first before
running this manual calibration (see 
Auto calibrations on page 46).
1.Press Calibrate on the Printing page, then press Manual Calibrations in the menu.
2.Press Manual Bidi Registration to proceed.
The control panel displays this prompt:
Print a manual bidi registration page?
3.Press Yes..
The control panel displays controls that enable you to position the registration pattern on the
media. This enables you to feed the same sheet of media into the printer multiple times without
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							overprinting previous patterns. For best quality when printing on rigid sheet-fed media, position
the pattern approximately 20 cm (8 in) from the edge.
4.Use the control panel controls to position the pattern, then press Proceed.
The printer prints the registration pattern, then prompts you to advance the media so you can
inspect it.
5.Advance the media by pressing Move Belt Forward, then press Proceed.
The control panel displays this prompt:
Bidi registration Head 1: 0
6.Examine the BiDi Registration pattern for the current head, and determine which pattern is the
closest to perfectly aligned.
Use a printer’s loupe (10X magnification or higher) to select the pattern, since the lines in the
patterns may be difficult to see.
7.Press the ▲ or ▼ control panel keys repeatedly until the number next to the pattern that is
closest to aligned perfectly is displayed.
For example, if pattern +2.0 is the closest aligned, press Proceed to change the display to:
Bidi registration Head 1: +2
If a printhead is extremely out of alignment, there may be no pattern in alignment. Since the
vertical bars are nominally five pixels apart, you can add +10 or -10 to a pattern number to shift
the colored bars right or left by one black bar. Alternatively, you can perform the BiDi
Registration repeatedly, which will move the head in smaller increments, until the head is
aligned.
8.Press the ▲ button.
The control panel message increments the head number by one.
9.Repeat steps 4 through 6 for each of the heads.
When you have entered registration values for all heads, the control panel displays this
message:
Registration Successful
Printhead X Calibration
Precise positioning of each drop of ink is essential for optimal print quality. This is possible only if you
register all printheads in the printhead assembly to each other in the X (along the length of the platen)
direction.
This is a two-part process:
●Print a registration pattern.
●Enter the X registration data for each head.
NOTE:This is the manual version of AutoH2H Calibration (see Auto calibrations on page 46).
1.Press Calibrate from the Printing page, then press Manual Calibrations in the menu.
2.Press Printhead X Calibration in the menu.
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							The control panel asks whether you want to print a manual head-to-head calibration page.
●If you need to print a new calibration pattern, press Proceed. The printer prints a calibration
page.
When the calibration page has printed, the control panel displays this prompt:
Take readings from left side of pattern.
●If you have a calibration pattern from a recent print, you can use it to calibrate the heads.
Press Cancel and go to the next step. (For best results, do not use a previously-printed
pattern, print a new pattern.)
3.Press Proceed..
The control panel displays this message:
X Direction Registration Head 2: +0
4.Examine the X direction pattern (in the left-hand group of patterns) for the current head, and
determine which pattern of colored and black lines are the closest to perfectly aligned.
Use a printer’s loupe or magnifying glass (10x magnification or higher) if the patterns are difficult
to see.
5.Press the ▲ or ▼ control panel keys repeatedly until the number next to the pattern that is
closest to aligned perfectly is displayed.
For example, if pattern -1 is the closest aligned, press the ▼ button to change the display to:
X Direction Registration Head 2: -1
If a printhead is extremely out of alignment, there may be no pattern in alignment. Since the
black vertical bars are five pixels apart, you can add +5 or -5 to a pattern number to shift the
colored bars up or down by one black bar. Alternatively, you can repeatedly perform the X
calibration, which will move the head in smaller increments, until the head is aligned.
6.Press Proceed.
The control panel message increments the head number by one.
7.Repeat steps 4 through 6 for each of the heads.
When you have entered registration values for all of the patterns, the control panel displays this
message:
Registration successful.
Manual Jet Mapping
Jets that are missing or misfiring are usually detected by the AutoJet calibration. Alternatively, you
can map out jets manually using the Manual Jet Mapping function. You may want to manually map
weak or misdirected jets that AutoJet does not substitute.
TIP:AutoJet is the automatic version of this calibration (see AutoJet on page 45).
TIP:For best results, print the prime bars and purge the printheads as necessary to ensure the
maximum number of working jets. See 
Ink page on page 35 for instructions.
1.Press Calibrate from the Printing page, then press Manual Calibrations in the menu.
2.Press Manual Jet Mapping in the menu.
The control panel displays this message:
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							Print Jet Map?
If you have a calibration pattern from a recent print, you can use it to calibrate the heads. Press
Cancel and go to the next step. Otherwise, press Proceed..
The printer prints a jet map test pattern.
If a line segment is missing or broken, the jet number shown next to it is out. A code letter if
present provides further information:
●R — no replacement
●S — user disqualified “soft” jetout
●H — user disqualified “hard” jetout
●D — disqualified (and replaced) by AutoJet
3.When the calibration pattern has printed, the control panel displays a menu with the following
options:
●Report individual soft bad jets — enables you to report a “soft” bad jet, which can be
automatically reenabled if AutoJet finds it working.
●Report individual hard bad jets — enables you to report a “hard” bad jet, which will not be
checked or reenabled by AutoJet.
●Clear individual bad jets — enables you to clear (mark as good) a jet.
●View current bad jets — lists the bad jets on a given printhead.
●Clear all bad jets for a head — clears (marks as good) all jets on a selected head currently
marked as unusable.
●Clear all bad jets — clears (marks as good) all jets currently marked as unusable.
A “soft” bad jet is a jet that you believe is temporarily out, based on past performance. A “hard”
bad jet is a jet that you believe is permanently out.
Select an option and follow the corresponding procedure below.
Report Individual Bad Jets
When you select Report Individual Bad Jets, the control panel displays the following prompt:
Head 1: Press Proceed to report a bad jet.
1.Press ▲ and ▼ to select a head number, then press Proceed (►).
The control panel displays a numeric keyboard that you can use to enter the number of the bad
jet.
2.Enter the jet number, then press Enter.
3.When you are finished entering jet numbers, press Cancel.
The control panel displays the head selection message again.
4.Press ▲ and ▼ to select the next head number, then press Proceed (►).
5.Repeat steps 2 through 4 for each head containing bad jets you want to report.
6.When you are finished reporting bad jets, press Cancel.
The control panel displays the previous menu.
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							Clear Individual Bad Jets
When you select Clear Individual Bad Jets, the control panel displays the following prompt:
Head 1: Press Proceed (►) to clear a bad jet.
1.Press ▲ and ▼ to select a head number, then press Proceed (►).
The control panel displays a numeric keyboard that you can use to enter the number of the bad
jet.
2.Enter the jet number, then press Enter.
3.When you are finished entering jet numbers, press Cancel.
The control panel displays the head selection message again.
4.Press ▲ and ▼ to select the next head number, then press Proceed.
5.Repeat steps 2 through 4 for each head containing bad jets you want to clear.
6.When you are finished clearing bad jets, press Cancel.
The control panel displays the previous menu.
View Current Bad Jets
When you select View Current Bad Jets, the control panel displays the following prompt:
Head 1: Press Proceed to view bad jets.
1.Press ▲ and ▼ to select a head number, then press Proceed (►).
The control panel displays a message that lists the bad jets by number.
2.Press Proceed (►) to return to the head selection screen.
3.Repeat steps 1 and 2 for each head you want to check for bad jets.
4.When you are finished viewing bad jets, press Cancel.
The control panel displays the previous menu.
Clear All Bad Jets for a Head
When you select Clear All Bad Jets for a Head, the control panel displays the following prompt:
Head 1: Press Proceed to clear all bad jets.
1.Press ▲ and ▼ to select a head number, then press ► (Proceed).
The control panel asks you to confirm your selection.
2.Press ►.
The control panel asks whether you want to clear the hard bad jets as well as the soft bad jets. A
“soft” bad jet is a jet that you believe is temporarily out, based on past performance. A “hard” bad
jet is a jet that you believe is permanently out.
3.Press ► to clear the hard and soft jets. Press X to clear the soft jets only.
The control panel reports the number of jets that were cleared on the selected printhead.
4.Press ►.
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							The head selection screen appears.
5.Repeat steps 1 through 4 for any other printhead, or press n to return to the menu.
Clear All Bad Jets
When you select Clear All Bad Jets, the control panel displays the following prompt:
Are you sure you want to clear ALL reported bad jets?
●Press Cancel to cancel this function, or
●Press Proceed. The control panel displays this message:
Do you want to clear the hard bad jets?
●Press No to clear the soft bad jets only, or
●Press Yes to clear both the hard and soft jets.
The control panel displays this message:
All reported bad jets have been cleared.
▲Press Proceed (►).
When you have finished mapping jets, the following summary appears on the control panel:
x soft jets currently reported bad. x hard jets currently reported bad. x new soft bad jets reported.
x new hard bad jets reported. x previous soft bad jets cleared. x previous hard bad jets cleared.
where x is the number of jets.
Default Registration Data
This option enables you to reset bidi registration, head-to-head registration, or jet mapping data, or
any combination of them. After running this option, the deleted calibration values must be
reestablished by running the calibrations.
Unfixed Jets Report
The Unfixed Jets Report displays a table showing, for each print mode, which colors are printing with
non-working inkjets that are not being automatically replaced with working jets by AutoJet mapping
(“unfixed” inkjets). For each combination of ink color and print mode, “No” means there are no unfixed
jets, “Yes” means there are unfixed jets.
Linearization
As the density of an image varies from highlights to shadows, or from lighter tints to darker tints, the
printer should accurately reproduce these areas in a predictable, or linear, fashion. The process of
linearization (or color calibration) involves printing and reading color test patches, and calibrating the
printer to ensure that the expected and printed densities will match. This in turn will ensure optimal
color matching.
Color calibration is a feature of the RIP connected to the printer. Refer to the documentation that
accompanies the RIP for further information.
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