[gnome-user-docs] Add some intial documentation and figures for color management



commit d75751ee02d805358e1a3ceafaa973569419253c
Author: Richard Hughes <richard hughsie com>
Date:   Wed Aug 24 21:49:11 2011 +0100

    Add some intial documentation and figures for color management

 gnome-help/C/color-assignprofiles.page             |   46 +++++++++
 gnome-help/C/color-calibrate-camera.page           |   38 ++++++++
 gnome-help/C/color-calibrate-printer.page          |   48 ++++++++++
 gnome-help/C/color-calibrate-scanner.page          |   35 +++++++
 gnome-help/C/color-calibrate-screen.page           |   45 +++++++++
 .../C/color-calibrationcharacterization.page       |   63 ++++++++++++
 gnome-help/C/color-calibrationdevices.page         |   41 ++++++++
 gnome-help/C/color-calibrationtargets.page         |   47 +++++++++
 gnome-help/C/color-canshareprofiles.page           |   38 ++++++++
 gnome-help/C/color-gettingprofiles.page            |   43 +++++++++
 gnome-help/C/color-missingvcgt.page                |   29 ++++++
 gnome-help/C/color-notspecifiededid.page           |   39 ++++++++
 gnome-help/C/color-whatisprofile.page              |   39 ++++++++
 gnome-help/C/color-why-calibrate.page              |   41 ++++++++
 gnome-help/C/color-whyimportant.page               |  100 ++++++++++++++++++++
 gnome-help/C/color.page                            |   36 +++++++
 gnome-help/C/figures/color-average.png             |  Bin 0 -> 16381 bytes
 gnome-help/C/figures/color-camera.png              |  Bin 0 -> 110839 bytes
 gnome-help/C/figures/color-display.png             |  Bin 0 -> 103602 bytes
 gnome-help/C/figures/color-printer.png             |  Bin 0 -> 96610 bytes
 gnome-help/C/figures/color-profile-default.png     |  Bin 0 -> 16034 bytes
 gnome-help/C/hardware.page                         |    1 +
 gnome-help/Makefile.am                             |   21 ++++
 23 files changed, 750 insertions(+), 0 deletions(-)
---
diff --git a/gnome-help/C/color-assignprofiles.page b/gnome-help/C/color-assignprofiles.page
new file mode 100644
index 0000000..0b6aa03
--- /dev/null
+++ b/gnome-help/C/color-assignprofiles.page
@@ -0,0 +1,46 @@
+<page xmlns="http://projectmallard.org/1.0/";
+      type="topic"
+      id="color-assignprofiles">
+
+  <info>
+    <link type="guide" xref="hardware#color"/>
+    <link type="seealso" xref="color-whatisprofile"/>
+    <link type="seealso" xref="color-whycalibrate"/>
+    <desc>Look in <guiseq><gui>System Settings</gui><gui>Color</gui></guiseq> for the option to change this.</desc>
+    <credit type="author">
+      <name>Richard Hughes</name>
+      <email>richard hughsie com</email>
+    </credit>
+    <include href="legal.xml" xmlns="http://www.w3.org/2001/XInclude"/>
+  </info>
+
+  <title>How do I assign profiles to devices?</title>
+
+  <p>
+    Open <guiseq><gui>System Settings</gui><gui>Color</gui></guiseq>,
+    and click the device that you wish to add a profile to.
+  </p>
+  <p>
+    By clicking <gui>Add profile</gui> you can select an existing
+    profile or import a new file.
+  </p>
+  <p>
+    Each device can have multiple profiles assigned to it, but only one
+    profile can be the <em>default</em> profile.
+    The default profile is used when there is no extra information to
+    allow the profile to be chosen automatically.
+    An example of this automatic selection would be if one profile was
+    created for glossy paper and another plain paper.
+  </p>
+
+  <figure>
+    <desc>You can make a profile default by changing it with the radio button.</desc>
+    <media type="image" mime="image/png" src="figures/color-profile-default.png"/>
+  </figure>
+
+  <p>
+    If calibration hardware is connected the <gui>Calibrate...</gui>
+    button will create a new profile.
+  </p>
+
+</page>
diff --git a/gnome-help/C/color-calibrate-camera.page b/gnome-help/C/color-calibrate-camera.page
new file mode 100644
index 0000000..c371b7e
--- /dev/null
+++ b/gnome-help/C/color-calibrate-camera.page
@@ -0,0 +1,38 @@
+<page xmlns="http://projectmallard.org/1.0/";
+      type="topic"
+      id="color-calibrate-camera">
+
+  <info>
+    <link type="guide" xref="color#calibration"/>
+    <link type="seealso" xref="color-calibrationtargets" />
+    <link type="seealso" xref="color-calibrate-printer" />
+    <link type="seealso" xref="color-calibrate-scanner" />
+    <link type="seealso" xref="color-calibrate-screen" />
+    <desc>Calibrating your camera is important to capture accurate colors.</desc>
+    <credit type="author">
+      <name>Richard Hughes</name>
+      <email>richard hughsie com</email>
+    </credit>
+    <include href="legal.xml" xmlns="http://www.w3.org/2001/XInclude"/>
+  </info>
+
+  <title>How do I calibrate my camera?</title>
+
+  <p>
+    Camera devices are calibrated by taking a photograph of a target
+    under the desired lighting conditions.
+    By converting the RAW file to a TIFF file, it can be used to
+    calibrate the camera device in the color control panel.
+  </p>
+
+  <note style="tip">
+    <p>
+      The resulting profile is only valid under the lighting condition
+      that you aquired the original image from.
+      This means you might need to profile several times for
+      <em>studio</em>, <em>bright sunlight</em> and <em>cloudy</em>
+      lighting conditions.
+    </p>
+  </note>
+
+</page>
diff --git a/gnome-help/C/color-calibrate-printer.page b/gnome-help/C/color-calibrate-printer.page
new file mode 100644
index 0000000..ea4d963
--- /dev/null
+++ b/gnome-help/C/color-calibrate-printer.page
@@ -0,0 +1,48 @@
+<page xmlns="http://projectmallard.org/1.0/";
+      type="topic"
+      id="color-calibrate-printer">
+
+  <info>
+    <link type="guide" xref="color#calibration"/>
+    <link type="seealso" xref="color-calibrate-scanner" />
+    <link type="seealso" xref="color-calibrate-screen" />
+    <link type="seealso" xref="color-calibrate-camera" />
+    <desc>Calibrating your printer is important to print accurate colors.</desc>
+    <credit type="author">
+      <name>Richard Hughes</name>
+      <email>richard hughsie com</email>
+    </credit>
+    <include href="legal.xml" xmlns="http://www.w3.org/2001/XInclude"/>
+  </info>
+
+  <title>How do I calibrate my printer?</title>
+
+  <p>
+    There are two ways to profile a printer device:
+  </p>
+
+  <list>
+    <item><p>Using a photospectrometer device like the Pantone ColorMunki</p></item>
+    <item><p>Downloading a printing a reference file from a color company</p></item>
+  </list>
+
+  <p>
+    Using a color company to generate a printer profile is usually the
+    cheapest option if you only have one or two different paper types.
+    By downloading the reference chart from the companies website you
+    can then send them back the print in a padded envelope where they
+    will scan the paper, generate the profile and email you back an
+    accurate ICC profile.
+  </p>
+  <p>
+    Using an expensive device such as a ColorMunki works out cheaper only
+    if you are profiling a large number of ink sets or paper types.
+  </p>
+
+  <note style="tip">
+    <p>
+      If you change your ink supplier, make sure you recalibrate the printer!
+    </p>
+  </note>
+
+</page>
diff --git a/gnome-help/C/color-calibrate-scanner.page b/gnome-help/C/color-calibrate-scanner.page
new file mode 100644
index 0000000..e8fea02
--- /dev/null
+++ b/gnome-help/C/color-calibrate-scanner.page
@@ -0,0 +1,35 @@
+<page xmlns="http://projectmallard.org/1.0/";
+      type="topic"
+      id="color-calibrate-scanner">
+
+  <info>
+    <link type="guide" xref="color#calibration"/>
+    <link type="seealso" xref="color-calibrationtargets" />
+    <link type="seealso" xref="color-calibrate-printer" />
+    <link type="seealso" xref="color-calibrate-screen" />
+    <link type="seealso" xref="color-calibrate-camera" />
+    <desc>Calibrating your scanner is important to capture accurate colors.</desc>
+    <credit type="author">
+      <name>Richard Hughes</name>
+      <email>richard hughsie com</email>
+    </credit>
+    <include href="legal.xml" xmlns="http://www.w3.org/2001/XInclude"/>
+  </info>
+
+  <title>How do I calibrate my scanner?</title>
+
+  <p>
+    You scan in your target file and save it as an uncompressed TIFF file.
+    You can then click <gui>Calibrate...</gui> from
+    <guiseq><gui>System Settings</gui><gui>Color</gui></guiseq> to
+    create a profile for the device.
+  </p>
+
+  <note style="tip">
+    <p>
+      Scanner devices are incredibly stable over time and temperature
+      and do not usually need to be recalibrated.
+    </p>
+  </note>
+
+</page>
diff --git a/gnome-help/C/color-calibrate-screen.page b/gnome-help/C/color-calibrate-screen.page
new file mode 100644
index 0000000..ebbeba0
--- /dev/null
+++ b/gnome-help/C/color-calibrate-screen.page
@@ -0,0 +1,45 @@
+<page xmlns="http://projectmallard.org/1.0/";
+      type="topic"
+      id="color-calibrate-screen">
+
+  <info>
+    <link type="guide" xref="color#calibration"/>
+    <link type="seealso" xref="color-calibrate-printer" />
+    <link type="seealso" xref="color-calibrate-scanner" />
+    <link type="seealso" xref="color-calibrate-camera" />
+    <desc>Calibrating your screen is important to display accurate colors.</desc>
+    <credit type="author">
+      <name>Richard Hughes</name>
+      <email>richard hughsie com</email>
+    </credit>
+    <include href="legal.xml" xmlns="http://www.w3.org/2001/XInclude"/>
+  </info>
+
+  <title>How do I calibrate my screen?</title>
+
+  <p>
+    Calibrating your screen is very easy to do and should be a hard
+    requirement if you're involved in computer design or artwork.
+  </p>
+  <p>
+    By using a device called colorimeter you accurately measure the
+    different colors that your screen is able to display.
+    By running <guiseq><gui>System Settings</gui><gui>Color</gui></guiseq>
+    you can easily create a profile, and the wizard will show you how
+    to attach the colorimeter device and what settings to adjust.
+  </p>
+
+  <note style="tip">
+    <p>
+      Screens change all the time - the backlight in a TFT will half in
+      brightness approximately every 18 months, and will get yellower
+      as it gets older.
+      This means you should recalibrate your screen when the [!] icon
+      appears in the color control panel.
+    </p>
+    <p>
+      LED screens also change over time, but a much slower rate than TFTs.
+    </p>
+  </note>
+
+</page>
diff --git a/gnome-help/C/color-calibrationcharacterization.page b/gnome-help/C/color-calibrationcharacterization.page
new file mode 100644
index 0000000..0f1109d
--- /dev/null
+++ b/gnome-help/C/color-calibrationcharacterization.page
@@ -0,0 +1,63 @@
+<page xmlns="http://projectmallard.org/1.0/";
+      type="topic"
+      id="color-calibrationcharacterization">
+
+  <info>
+
+    <link type="guide" xref="color#calibration"/>
+
+    <desc>Calibration and characterization are different things entirely.</desc>
+
+    <credit type="author">
+      <name>Richard Hughes</name>
+      <email>richard hughsie com</email>
+    </credit>
+    <include href="legal.xml" xmlns="http://www.w3.org/2001/XInclude"/>
+  </info>
+
+  <title>What's the difference between calibration and characterization?</title>
+  <p>
+    Many people are initially confused about the difference between calibration
+    and characterization.
+    Calibration is the process of modifying the color behavior of a device.
+    This is typically done using two mechanisms:
+  </p>
+  <list>
+    <item><p>Changing controls or internal settings that it has</p></item>
+    <item><p>Applying curves to its color channels</p></item>
+  </list>
+  <p>
+    The idea of calibration is to put a device is a defined state with regard
+    to its color response.
+    Often this is used as a day to day means of maintaining reproducible behavior.
+    Typically calibration will be stored in device or systems specific file
+    formats that record the device settings or per-channel calibration curves.
+  </p>
+  <p>
+    Characterization (or profiling) is <em>recording</em> the way
+    a device reproduces or responds to color.
+    Typically the result is stored in a device ICC profile.
+    Such a profile does not in itself modify color in any way.
+    It allows a system such as a CMM (Color Management Module) or a color aware
+    application to modify color when combined with another device profile.
+    Only by knowing the characteristics of two devices, can a way of
+    transferring color from one device representation to another be achieved.
+  </p>
+  <note>
+    <p>
+      Note that a characterization (profile) will only be valid for a device
+      if it is in the same state of calibration as it was when it was
+      characterized.
+    </p>
+  </note>
+  <p>
+    In the case of display profiles there is some additional confusion because
+    often the calibration information is stored in the profile for convenience.
+    By convention it is stored in a tag called the <em>vcgt</em> tag.
+    Although it is stored in the profile, none of the normal ICC based tools
+    or applications are aware of it, or do anything with it.
+    Similarly, typical display calibration tools and applications will not be
+    aware of, or do anything with the ICC characterization (profile) information.
+  </p>
+
+</page>
diff --git a/gnome-help/C/color-calibrationdevices.page b/gnome-help/C/color-calibrationdevices.page
new file mode 100644
index 0000000..05ce7bc
--- /dev/null
+++ b/gnome-help/C/color-calibrationdevices.page
@@ -0,0 +1,41 @@
+<page xmlns="http://projectmallard.org/1.0/";
+      type="topic"
+      id="color-calibrationdevices">
+
+  <info>
+
+    <link type="guide" xref="color#calibration"/>
+
+    <desc>We support a huge number of calibration devices.</desc>
+
+    <credit type="author">
+      <name>Richard Hughes</name>
+      <email>richard hughsie com</email>
+    </credit>
+    <include href="legal.xml" xmlns="http://www.w3.org/2001/XInclude"/>
+  </info>
+
+  <title>What color measuring instruments are supported?</title>
+
+  <p>
+    GNOME relies on the ArgyllCMS project to support color instruments.
+    Thus the following display measuring instruments are supported:
+  </p>
+
+  <list>
+    <item><p>Gretag-Macbeth Eye-One Pro (spectrometer)</p></item>
+    <item><p>Gretag-Macbeth Eye-One Monitor (spectrometer)</p></item>
+    <item><p>Gretag-Macbeth Eye-One Display 1, 2 or LT (colorimeter)</p></item>
+    <item><p> X-Rite ColorMunki Design or Photo (spectrometer)</p></item>
+    <item><p> X-Rite ColorMunki Create (colorimeter)</p></item>
+    <item><p>Pantone Huey (colorimeter)</p></item>
+    <item><p>MonacoOPTIX (colorimeter)</p></item>
+    <item><p>ColorVision Spyder 2 and 3 (colorimeter)</p></item>
+    <item><p>ColorimÃtre HCFR (colorimeter)</p></item>
+  </list>
+
+  <note style="tip">
+   <p>The Pantone Huey is currently the cheapest and best supported hardware in Linux.</p>
+  </note>
+
+</page>
diff --git a/gnome-help/C/color-calibrationtargets.page b/gnome-help/C/color-calibrationtargets.page
new file mode 100644
index 0000000..457be61
--- /dev/null
+++ b/gnome-help/C/color-calibrationtargets.page
@@ -0,0 +1,47 @@
+<page xmlns="http://projectmallard.org/1.0/";
+      type="topic"
+      id="color-calibrationtargets">
+
+  <info>
+
+    <link type="guide" xref="color#calibration"/>
+
+    <desc>Calibration targets are needed to do scanner and camera profiling.</desc>
+
+    <credit type="author">
+      <name>Richard Hughes</name>
+      <email>richard hughsie com</email>
+    </credit>
+    <include href="legal.xml" xmlns="http://www.w3.org/2001/XInclude"/>
+  </info>
+
+  <title>Which target types are supported?</title>
+
+  <p>
+    The following types of targets are supported:
+  </p>
+
+  <list>
+    <item><p>CMP DigitalTarget</p></item>
+    <item><p>ColorChecker 24</p></item>
+    <item><p>ColorChecker DC</p></item>
+    <item><p>ColorChecker SG</p></item>
+    <item><p>i1 RGB Scan 14</p></item>
+    <item><p>LaserSoft DC Pro</p></item>
+    <item><p>QPcard 201</p></item>
+    <item><p>IT8.7/2</p></item>
+  </list>
+
+  <note style="tip">
+    <p>
+      You can purchase targets from well-known vendors like KODAK, X-Rite
+      and LaserSoft in various online shops.
+    </p>
+    <p>
+      Alternatively you can buy
+      targets from <link href="http://www.targets.coloraid.de/";>Wolf Faust</link>
+      at a very fair price.
+    </p>
+  </note>
+
+</page>
diff --git a/gnome-help/C/color-canshareprofiles.page b/gnome-help/C/color-canshareprofiles.page
new file mode 100644
index 0000000..2bf5a99
--- /dev/null
+++ b/gnome-help/C/color-canshareprofiles.page
@@ -0,0 +1,38 @@
+<page xmlns="http://projectmallard.org/1.0/";
+      type="topic"
+      id="color-canshareprofiles">
+
+  <info>
+    <link type="guide" xref="color#calibration"/>
+    <link type="seealso" xref="color-whatisprofile"/>
+    <desc>Sharing color profiles is nevera good idea as hardware changes over time.</desc>
+    <credit type="author">
+      <name>Richard Hughes</name>
+      <email>richard hughsie com</email>
+    </credit>
+    <include href="legal.xml" xmlns="http://www.w3.org/2001/XInclude"/>
+  </info>
+
+  <title>Can I share my color profile?</title>
+
+  <p>
+    Color profiles that you have created yourself are specific to the
+    hardware that you calibrated for.
+    My DreamColor LP2480zx has been powered for a few hundred hours, and
+    is going to have a very different color profile to a similar display
+    with the next serial number if it's been lit for a thousand hours.
+  </p>
+  <p>
+    This means if you share your color profile with somebody, you might
+    be getting them <em>closer</em> to calibration, but it's misleading
+    at best to say that thier display is calibrated.
+  </p>
+
+  <note style="warning">
+    <p>
+      You should carefully check the redistribution conditions for profiles
+      downloaded from vendor websites or that were created on your behalf.
+    </p>
+  </note>
+
+</page>
diff --git a/gnome-help/C/color-gettingprofiles.page b/gnome-help/C/color-gettingprofiles.page
new file mode 100644
index 0000000..12e39b7
--- /dev/null
+++ b/gnome-help/C/color-gettingprofiles.page
@@ -0,0 +1,43 @@
+<page xmlns="http://projectmallard.org/1.0/";
+      type="topic"
+      id="color-gettingprofiles">
+
+  <info>
+    <link type="guide" xref="color#profiles"/>
+    <link type="seealso" xref="color-why-calibrate"/>
+    <link type="seealso" xref="color-whatisprofile"/>
+    <link type="seealso" xref="color-missingvcgt"/>
+    <desc>Color profiles are provided by vendors and can be generated yourself.</desc>
+    <credit type="author">
+      <name>Richard Hughes</name>
+      <email>richard hughsie com</email>
+    </credit>
+    <include href="legal.xml" xmlns="http://www.w3.org/2001/XInclude"/>
+  </info>
+
+  <title>Where do I get color profiles?</title>
+
+  <p>
+    The best way to get profiles is to generate them yourself, although
+    this does require some initial outlay.
+  </p>
+  <p>
+    Many manufacturers do try to provide color profiles for devices,
+    although sometimes they are wrapped up in <em>driver bundles</em>
+    which you may need to download, extract and then search for the
+    color profiles.
+  </p>
+  <p>
+    Some manufacturers do not provide accurate profiles for the hardware
+    and the profiles are best avoided.
+    A good clue is to download the profile, and if the creation date is
+    more than a year before the date you bought the device then it's
+    likely dummy data generated that is useless.
+  </p>
+
+  <p>
+    See <link xref="color-why-calibrate"/> for information on why vendor
+    suplied profiles are often worse than useless.
+  </p>
+
+</page>
diff --git a/gnome-help/C/color-missingvcgt.page b/gnome-help/C/color-missingvcgt.page
new file mode 100644
index 0000000..5627109
--- /dev/null
+++ b/gnome-help/C/color-missingvcgt.page
@@ -0,0 +1,29 @@
+<page xmlns="http://projectmallard.org/1.0/";
+      type="topic"
+      id="color-missingvcgt">
+
+  <info>
+    <link type="guide" xref="color#problems"/>
+    <link type="seealso" xref="color-gettingprofiles"/>
+    <desc>Whole-screen color correction modifies all the screen colors on all windows.</desc>
+    <credit type="author">
+      <name>Richard Hughes</name>
+      <email>richard hughsie com</email>
+    </credit>
+    <include href="legal.xml" xmlns="http://www.w3.org/2001/XInclude"/>
+  </info>
+
+  <title>Missing information for whole-screen color correction?</title>
+  <p>
+    Unfortunately, many vendor-supplied ICC profiles do not include the
+    information required for whole-screen color correction.
+    These profiles can still be useful for applications that can do color
+    compensation, but you will not see all the colors of your screen change.
+  </p>
+  <p>
+    In order to create a display profile, which includes both calibration and
+    characterisation data, you will need to use a special color measuring
+    instruments callled a colorimeter or a spectrometer.
+  </p>
+
+</page>
diff --git a/gnome-help/C/color-notspecifiededid.page b/gnome-help/C/color-notspecifiededid.page
new file mode 100644
index 0000000..363df91
--- /dev/null
+++ b/gnome-help/C/color-notspecifiededid.page
@@ -0,0 +1,39 @@
+<page xmlns="http://projectmallard.org/1.0/";
+      type="topic"
+      id="color-notspecifiededid">
+
+  <info>
+    <link type="guide" xref="color#problems"/>
+    <link type="guide" xref="color-gettingprofiles"/>
+    <link type="guide" xref="color-why-calibrate"/>
+    <desc>Default monitor profiles do not have a calibration date.</desc>
+    <credit type="author">
+      <name>Richard Hughes</name>
+      <email>richard hughsie com</email>
+    </credit>
+    <include href="legal.xml" xmlns="http://www.w3.org/2001/XInclude"/>
+  </info>
+
+  <title>Why don't the default monitor profiles have a calibration expiry?</title>
+  <p>
+    The default color profile used for each monitor is generated
+    automatically based on the display EDID which is stored in a memory
+    chip inside the monitor.
+    The EDID only gives us a snapshot of the available colors the monitor
+    was capable of displaying when it was manufactured, and does not
+    contain much other information for color correction.
+  </p>
+
+  <figure>
+    <desc>As the EDID cannot be updated, it has no expiry date.</desc>
+    <media type="image" mime="image/png" src="figures/color-profile-default.png"/>
+  </figure>
+
+  <note style="tip">
+    <p>
+      Getting a profile from the monitor vendor or creating a profile
+      youself would lead to more accurate color correction.
+    </p>
+  </note>
+
+</page>
diff --git a/gnome-help/C/color-whatisprofile.page b/gnome-help/C/color-whatisprofile.page
new file mode 100644
index 0000000..90d3360
--- /dev/null
+++ b/gnome-help/C/color-whatisprofile.page
@@ -0,0 +1,39 @@
+<page xmlns="http://projectmallard.org/1.0/";
+      type="topic"
+      id="color-whatisprofile">
+
+  <info>
+    <link type="guide" xref="color#profiles"/>
+    <desc>A color profile is a simple file that expresses a color space or device response.</desc>
+    <credit type="author">
+      <name>Richard Hughes</name>
+      <email>richard hughsie com</email>
+    </credit>
+    <include href="legal.xml" xmlns="http://www.w3.org/2001/XInclude"/>
+  </info>
+
+  <title>What is a color profile?</title>
+
+  <p>
+    A color profile is a set of data that characterizes either a device
+    such as a projector or a color space such as sRGB.
+  </p>
+  <p>
+    Most color profiles are in the form of an ICC profile, which is a
+    small file with a <input>.ICC</input> or <input>.ICM</input> file
+    extension.
+  </p>
+  <p>
+    Color profiles can be embedded into images to specify the gamut range
+    of the data.
+    This ensures that users see the same colors on different devices.
+  </p>
+  <p>
+    Every device that is processing color should have it's own ICC
+    profile and when this is achieved the system is said to have an
+    <em>end-to-end color-managed workflow</em>.
+    With this kind of workflow you can be sure that colors are not being
+    lost or modified.
+  </p>
+
+</page>
diff --git a/gnome-help/C/color-why-calibrate.page b/gnome-help/C/color-why-calibrate.page
new file mode 100644
index 0000000..560a37b
--- /dev/null
+++ b/gnome-help/C/color-why-calibrate.page
@@ -0,0 +1,41 @@
+<page xmlns="http://projectmallard.org/1.0/";
+      type="topic"
+      id="color-why-calibrate">
+
+  <info>
+    <link type="guide" xref="color#calibration"/>
+    <desc>Calibrating is important if you care about the colors you display or print.</desc>
+    <credit type="author">
+      <name>Richard Hughes</name>
+      <email>richard hughsie com</email>
+    </credit>
+    <include href="legal.xml" xmlns="http://www.w3.org/2001/XInclude"/>
+  </info>
+
+  <title>Why do I need to do calibration myself?</title>
+
+  <p>
+    Generic profiles are usually bad.
+    When a manufacturer creates a new model, they just take a few items
+    from the production line and average them together:
+  </p>
+
+  <media type="image" src="figures/color-average.png">
+    <p>Averaged profiles</p>
+  </media>
+
+  <p>
+    Display panels differ quite a lot from unit to unit and change
+    substantially as the display ages.
+    It is also more difficult for printers, as just changing the type
+    or weight of paper can invalidate the characterization state and
+    make the profile inaccurate.
+  </p>
+
+  <p>
+    The best way of ensuring the profile you have is accurate is by doing
+    the calibration yourself, or by letting an external company supply
+    you with a profile based on your exact characterization state.
+  </p>
+
+</page>
diff --git a/gnome-help/C/color-whyimportant.page b/gnome-help/C/color-whyimportant.page
new file mode 100644
index 0000000..5ca8bd4
--- /dev/null
+++ b/gnome-help/C/color-whyimportant.page
@@ -0,0 +1,100 @@
+<page xmlns="http://projectmallard.org/1.0/";
+      type="topic"
+      id="color-whyimportant">
+
+  <info>
+    <link type="guide" xref="color"/>
+    <desc>Color management is important for designers, photographers and artists.</desc>
+    <credit type="author">
+      <name>Richard Hughes</name>
+      <email>richard hughsie com</email>
+    </credit>
+    <include href="legal.xml" xmlns="http://www.w3.org/2001/XInclude"/>
+  </info>
+
+  <title>Why is color management important?</title>
+  <p>
+    Color management is the process of capturing a color using an input
+    device, displaying it on a screen, and printing it all whilst managing
+    the exact colors and the range of colors on each medium.
+  </p>
+
+  <p>
+    The need for color management is probably explained best with a
+    photograph of a bird on a frosty day in winter.
+  </p>
+
+  <figure>
+    <desc>A bird on a frosty wall as seen on the camera view-finder</desc>
+    <media type="image" mime="image/png" src="figures/color-camera.png"/>
+  </figure>
+
+  <p>
+    Displays typically over-saturate the blue channel, making the images
+    look cold.
+  </p>
+
+  <figure>
+    <desc>This is what the user sees on a typical business laptop screen</desc>
+    <media type="image" mime="image/png" src="figures/color-display.png"/>
+  </figure>
+
+  <p>
+    Notice how the white is not 'paper white' and the black of the eye
+    is now a muddy brown.
+  </p>
+
+  <figure>
+    <desc>This is what the user sees when printing on a typical inkjet printer</desc>
+    <media type="image" mime="image/png" src="figures/color-printer.png"/>
+  </figure>
+
+  <p>
+    The basic problem we have here is that each device is capable of
+    handling a different range of colors.
+    So while you might be able to take a photo of electric blue, most
+    printers are not going to be able to reproduce it.
+  </p>
+  <p>
+    Most image devices capture in RGB (Red, Green, Blue) and have
+    to convert to CMYK (Cyan, Magenta, Yellow, and Black) to print.
+    Another problem is that you can't have <em>white</em> ink, and so
+    the whiteness can only be as good as the paper color.
+  </p>
+
+  <p>
+    Another problem is units.
+    Without specifying the scale on which a color is measured, we don't
+    know if 100% red is near infrared or just the deepest red ink in the
+    printer.
+    What is 50% red on your display is probably something like 62% on my
+    display.
+    It's like telling a person that you've just driven 7 units of
+    distance, without the unit you don't know if that's 7 kilometers or
+    7 meters.
+  </p>
+
+  <p>
+    In color, we refer to the units as gamut. Gamut is essentually the
+    range of colors that can be reproduced.
+    A device like a DSLR camera might have a very large gamut, being able
+    to capture all the colors in a sunset, but a projector has a very
+    small gamut and all the colors are going to look "washed out".
+  </p>
+
+  <p>
+    In some cases we can <em>correct</em> the device response by altering
+    the data we sent to the device but in other cases where that's not
+    possible (you can't print electric blue) we need to show the user
+    what the result is going to look like.
+  </p>
+
+  <p>
+    For photographs it makes sense to use the full tonal range of a color
+    device, to be able to make smooth changes in color.
+    For other graphics you might want to match the color exactly, which
+    is important if you're trying to print a custom mug with the Red Hat
+    logo, that <em>has</em> to be the exact Red Hat Red.
+  </p>
+
+</page>
diff --git a/gnome-help/C/color.page b/gnome-help/C/color.page
new file mode 100644
index 0000000..4e0a5e5
--- /dev/null
+++ b/gnome-help/C/color.page
@@ -0,0 +1,36 @@
+<page xmlns="http://projectmallard.org/1.0/";
+      type="guide"
+      id="color">
+  <info>
+    <link type="guide" xref="prefs"/>
+    <link type="guide" xref="hardware" />
+
+    <credit type="author">
+      <name>Richard Hughes</name>
+      <email>richard hughsie com</email>
+    </credit>
+    <include href="legal.xml" xmlns="http://www.w3.org/2001/XInclude"; />
+
+    <desc>
+      <link xref="color-whyimportant">Why is this important</link>,
+      <link xref="color#profiles">Color profiles</link>,
+      <link xref="color#calibration">How to calibrate a device</link>...
+    </desc>
+
+  </info>
+
+  <title>Color management</title>
+
+  <section id="profiles" style="2column">
+    <title>Color profiles</title>
+  </section>
+
+  <section id="calibration" style="2column">
+    <title>Calibration</title>
+  </section>
+
+  <section id="problems" style="2column">
+    <title>Problems</title>
+  </section>
+
+</page>
diff --git a/gnome-help/C/figures/color-average.png b/gnome-help/C/figures/color-average.png
new file mode 100644
index 0000000..102d339
Binary files /dev/null and b/gnome-help/C/figures/color-average.png differ
diff --git a/gnome-help/C/figures/color-camera.png b/gnome-help/C/figures/color-camera.png
new file mode 100644
index 0000000..2c03c2b7
Binary files /dev/null and b/gnome-help/C/figures/color-camera.png differ
diff --git a/gnome-help/C/figures/color-display.png b/gnome-help/C/figures/color-display.png
new file mode 100644
index 0000000..121ed6b
Binary files /dev/null and b/gnome-help/C/figures/color-display.png differ
diff --git a/gnome-help/C/figures/color-printer.png b/gnome-help/C/figures/color-printer.png
new file mode 100644
index 0000000..6a8ffaf
Binary files /dev/null and b/gnome-help/C/figures/color-printer.png differ
diff --git a/gnome-help/C/figures/color-profile-default.png b/gnome-help/C/figures/color-profile-default.png
new file mode 100644
index 0000000..fe5e6a9
Binary files /dev/null and b/gnome-help/C/figures/color-profile-default.png differ
diff --git a/gnome-help/C/hardware.page b/gnome-help/C/hardware.page
index 28783f7..bfda370 100644
--- a/gnome-help/C/hardware.page
+++ b/gnome-help/C/hardware.page
@@ -18,6 +18,7 @@
       <link xref="hardware#problems">Hardware problems</link>,
       <link xref="printing">printers</link>,
       <link xref="power">power settings</link>,
+      <link xref="color">color management</link>,
       <link xref="bluetooth">Bluetooth</link>,
       <link xref="disk">disks</link>...
     </desc>
diff --git a/gnome-help/Makefile.am b/gnome-help/Makefile.am
index 2f1584d..b907eda 100644
--- a/gnome-help/Makefile.am
+++ b/gnome-help/Makefile.am
@@ -5,6 +5,11 @@ HELP_ID = gnome-help
 HELP_LINGUAS = ca de fi es gl hi nl sl sv vi
 
 HELP_MEDIA = \
+	figures/color-average.png \
+	figures/color-camera.png \
+	figures/color-display.png \
+	figures/color-printer.png \
+	figures/color-profile-default.png \
 	figures/gnome.png \
 	figures/gnome-searchtool.png \
 	figures/nautilus.png \
@@ -57,6 +62,22 @@ HELP_FILES = \
 	bluetooth-remove-connection.page \
 	bluetooth-send-file.page \
 	bluetooth-turn-on-off.page \
+	color.page \
+	color-assignprofiles.page \
+	color-calibrate-camera.page \
+	color-calibrate-printer.page \
+	color-calibrate-scanner.page \
+	color-calibrate-screen.page \
+	color-calibrationcharacterization.page \
+	color-calibrationdevices.page \
+	color-calibrationtargets.page \
+	color-canshareprofiles.page \
+	color-gettingprofiles.page \
+	color-missingvcgt.page \
+	color-notspecifiededid.page \
+	color-whatisprofile.page \
+	color-why-calibrate.page \
+	color-whyimportant.page \
 	clock.page \
 	clock-calendar.page \
 	clock-set.page \



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