Nikon Color Management user guide
Nikon Color Management
Nikon Color Management
Keeping Colors True
Turning Nikon CMS Off
CMYK
The Nikon Color Management System, or Nikon CMS, en sures that image data from Nikon scanners are re pro duced
consistently and accurately on monitors or print ers. With this
pow er ful tool, colors can be manipulated in a cal i brat ed RGB
color model before the data are passed to the host application. Profi les detailing the color char ac ter is tics of the chosen
color model and the output de vice (mon i tor or print er) ensure that colors will be reproduced ac cu rate ly in al most any
operating environment.
Keeping Colors True
Nikon CMS involves two categories of preferences, one
(“Gamma”) for use when Nikon CMS is off and the other
(“Color Man age ment”) for use when Nikon CMS is on.
“Gamma” specifi es how data from the scanner will be mod i fi ed for display on the monitor. Because monitor profi les
can not be used when Nikon CMS is off, this adjustment
must be made manually. “Color Management” is used to
turn Nikon CMS on and off and select the profi les for use
with the monitor and with the CMYK and calibrated RGB
color models when Nikon CMS is on.
Tur ning Nikon CMS Off
In general, much better results can be achieved with Nikon CMS on. It
may however be necessary to turn color management off to:
CMYK
Images can not be scanned in CMYK. If CMYK data are required, convert images to CMYK before saving them to disk. Note that images
can only be saved in CMYK if Nikon CMS is on (Nikon CMS is on by
default).
Preferences— Nikon Color Management
• Speed processing
If the computer has a slow CPU, the processing required for color
management may result in longer scan times. Try turning color management off for reduced scan times.
• Edit data from the scanner directly
Advanced users may want to turn Nikon CMS off to edit uncalibrated
RGB data from the scanner.
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How Nikon CMS Works
Creating Monitor Profi les
When image data are passed from an input device, such as
a scanner, to an output device, such as a monitor or printer,
color management ensures that the image displayed on the
output device “looks the same” as the original. To accomplish this task, the color management system must have
information about the color characteristics of both the input
and output devices, as well as the color space used for editing. The fi les containing this in for ma tion are called “ICC profi les.” Nikon Scan uses the fol low ing three types of profi le:
Input Profi les
Input profi les provide information on the input device, i.e.,
the Nikon scanner. Fixed pro fi les de tail ing the color char ac ter is tics of sup port ed Nikon scanners are provided with
Nikon Scan. An input profi le is se lect ed au to mat i cal ly based
on the model of scan ner used and the type of media (pos i tive or negative) being scanned.
Color-Space Profi les
Separate profi les are avail able for the RGB and CMYK color
models. Nikon Scan comes with a selection of profi les for
the RGB color model, while CMYK profi les for color print ers
are usually pro vid ed by the man u fac tur er. Color-space pro fi les are used when editing images in the scan win dow and
when making the fi nal scan.
Monitor Profi les
Monitor profi les are usually provided by the manufacturer,
although profi les for some common monitor types may be
included with the computer operating system. Monitor
profi les apply when images are displayed on a monitor, for
example when an image is displayed in the preview area or
an image win dow.
Preferences— Nikon Color Management
Creating Monitor Profi les
If desired, Adobe Photoshop can be used to create a monitor profi le for
a specifi c environment. This profi le can then be used in Nikon Scan.
For information on creating monitor profi les, see the doc u men ta tion
provided with Adobe Photoshop. This option is not avail able in Adobe
Photoshop LE.
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The Scanning Process
The illustration below shows the role Nikon CMS plays in
the scanning process. CMS profi les are shown in blue, user
op er a tions in red.
When Nikon CMS is on, uncalibrated RGB image data from
the scan ner are converted to grayscale or calibrated RGB,
de pend ing on the color model selected in the scan window.
RGB data are processed according to the profi le selected for
the calibrated RGB color space. These data are stored in
mem o ry so that the color model can be changed with out
per form ing an oth er pre view. Any changes made using the
color enhancement and Unsharp Mask tools also ap ply to
these data. When the im age is dis played in the pre view win dow, the mon i tor pro fi le is used to ensure that the preview
image is as true as pos si ble to the data in mem o ry.
When the Scan button is clicked to perform the fi nal scan,
the scan data are processed according to the selected colorspace profi le and any changes that were made using the
color en hance ment and Unsharp Mask tools in the scan
win dow. The data are then trans ferred to the host ap pli ca tion. Where pos si ble, the color-space pro fi le is trans ferred
to the host ap pli ca tion to geth er with the im age data. The
TWAIN in ter face used in Windows, how ev er, does not al low
profi les to be passed to an oth er ap pli ca tion, with the result
that under Win dows the pro fi le is only transferred to the
host when Nikon Scan is used as a “stand-alone” application
(note that profi le information is lost when the image is saved
in a format such as BMP that does not allow the profi le to
be recorded). When im ag es are dis played in im age win dows
in Nikon Scan, the monitor profi le en sures that the image on
the screen refl ects the orig i nal as close ly as pos si ble.
Before preview
Scanner Extras
Digital ICE4 Advanced
Scan Image Enhancer
Analog Gain
Film type selection
Color model and profi le
selection
Preferences— Nikon Color Management
Preview
Preview
Scanner
input profi le
Color-space
profi le
New color-
space profi le
Changes to color
model or color-
space profi le
Image processing
Curves
Color Balance
LCH Editor
Unsharp Mask
Monitor
profi le
Monitor
profi le
Processed tab
Natural tab
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Scan
Scan
Host application
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Scanning with Nikon CMS Off
If Use Nikon Color Management System is not selected in
the “Color Management” category, profi les can not be used
to ensure that the data from the scanner are reproduced ac cu rate ly when passed to another application or displayed in
the mon i tor. Be cause the color profi les required for a cal i brat ed RGB color space are not available when Nikon CMS is
off, images can only be scanned as uncalibrated RGB or grayscale. Similarly, the absence of a monitor profi le means that
gamma adjustment must be used to correct the image for
dis play on the monitor or for editing in another application.
These ad just ments to gamma are made in the “Gamma”
category of the “Pref er enc es” dialog.
The illustration below shows how scanning proceeds when
Nikon CMS is off. The image shown in the preview window
is ad just ed for display in the monitor ac cord ing to the value
cho sen for preview gamma in the “Gam ma” category. When
the Scan but ton is clicked, the main scan gamma and any
changes to curves and color balance are passed to the scan ner, where they are ap plied to scan data be fore the image is
trans ferred to the host ap pli ca tion (if Nikon Scan is used as
a “stand-alone” ap pli ca tion, the value for preview gam ma
is passed to the scan ner instead of main scan gamma). The
LCH Editor and Unsharp Mask tools can not be used when
Nikon CMS is off.
Scanner Extras
Digital ICE4 Advanced
Scan Image Enhancer
Analog Gain
Gamma adjustment
Preferences— Nikon Color Management
PreviewBefore preview
Preview
Image processing
Curves
Color Balance
Preview
gamma
Preview
gamma
Processed tab
Natural tab
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Scan
Scan
Main
scan
gamma
Host application
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Gamma
When the Use Nikon Color Management System option
in the “Color Management” category (
84) is off, the con-
trols in the “Gamma” category are used to adjust data from
the scanner so that they display correctly when previewed on
the monitor or opened in an oth er application.
Preview gamma
Preview gamma applies to the image displayed in the pre view area of the scan window. In general, preview gamma
is solely for display in the preview area and does not apply
to the image data that are passed to the host application
when the Scan button is clicked. There are two exceptions
to this rule, how ev er. The fi rst is when Nikon Scan is used as
a “stand-alone” application, the second when Use preview
gam ma is se lect ed as the main scan gamma option. In
these cases pre view gam ma is ap plied to im age data passed
to the host ap pli ca tion.
Preview gam ma de faults to a val ue of 1.8 on the Macintosh,
2.2 on Win dows com put ers. To choose a set ting suited to
the current monitor, adjust the value so that the pat terns of
gray lines and dots above the slider match in density. Gam ma can be set by en ter ing a value directly into the text box or
by moving the slider. When mak ing this ad just ment, set the
res o lu tion on the monitor to a low value such as 640 × 480
and sit as far away from the monitor as possible. To restore
the default setting for your platform, click Reset.
Preferences— Nikon Color Management
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