G7 calibration is conducted between the Fiery server calibration and
printing of profiling measurement patches.
G7 calibration is applied on the top of the Fiery server calibration.
Entering the G7 calibration process, you will select the patch layout for the P2P
target you wish to use, measure them, inspect the results, and make adjustments to
the settings, if needed.
The G7 specification defines standard grayscale curves that can be used
to create a common neutral appearance of output on different printers. G7
calibration adjusts the color output of a printer to the G7 specification, using
measurement data from a specific G7 target (P2P target). Fiery Color Profiler
Suite supports
printing and measuring different P2P targets that are used for G7 calibration. You
can measure with any supported measurement instrument, including inline measurement
instruments, in which case the process can become automated without user
interaction.
-
In the Patch layout window, select the G7 patch
set you want to use:
- P2P51 (the newer target,
a revision of the original)
- P2P25Xa (the original
target)
Note: The actual values used in
the targets are similar, but the newer version is a more precise version of
the G7 specification.
-
Click Print and measure the patch page.
-
Review the G7 gray
balance measurement results.
Because this is
the G7 calibration run, it is expected that the results are failing. It is
the measurements from this target that will be used to calculate the NPDC
curves necessary for G7 calibration.
The NPDC (Neutral
Print Density Curve) is displayed separately for CMY (composite) and K
(black). Gray balance is plotted as a*b*. In the table, the weighted average
must be less than 1.5 to show as green. The weighted maximum must be less
than 3 to show as green.
-
(Optional) Click
Correction options to display the correction curve,
and expose advanced options applied to the formation of the correction
curves.
You can choose to keep the
defaults or change them.
-
Click OK
to print the P2P patch page again with the NPDC curves applied.
-
Measure the patch pages and view
the G7 results.
-
If the G7 result is passing (all
results show in green), click Next. If the result is
failing (any result highlighted in red), then click
Iterate to repeat the process. Additional iterations
will not lead to better results. You can perform a maximum of four
iterations.
