Does your display look a little off? Not just too bright or too dim but perhaps some colors don't look as accurate as they should or the image tends to look a bit washed out at times. If so, then it's time to calibrate your display.
You can either calibrate your display by eye or by using a device called a color calibrator -- or colorimeter -- that you stick on the front of your display. If you have a colorimeter, then I'm going to assume you know how to use it and don't need to read a blog post on the topic. If you haven't plunked down $100 or more on a colorimeter, then I'm also going to assume you don't have any immediate plans to purchase such a device and would like to go about calibrating your monitor by eye.
Thankfully, it's easy to make adjustments by eye. If you don't get your display as fine tuned as you might with a colorimeter, as long as the image looks good to you, then I would classify the mission as accomplished.
Two notes before you get started:
The quickest and easiest way to calibrate your display is to stare at a number of test patterns and use your monitor's onscreen display (OSD) controls to adjust the contrast, brightness, color levels, sharpness, color temperature, and so on. A good resource for free test patterns is Lagom LCD monitor test pages. The site will lead you through a series of test patterns, which you use to adjust your monitor using the OSD controls -- the group of buttons located on the front or side of your display.
But what if you are using a laptop that doesn't have such buttons, you ask? Both Windows and Mac OS X feature utilities that step you through various calibration settings.
Now, you can always buy a hardware colorimeter like X-Rite ColorMunki Display or Datacolor SpyderX Pro to better calibrate your monitor but, if you have zero dollars to spend, here is some free software that will get the job done. Read: Best Color Picker for Windows. Before we begin. It’s important to understand the term Color Calibration. How to Calibrate Your Monitor. This wikiHow teaches you how to calibrate a computer monitor to ensure that your color and light settings are correct. Monitor calibration is important when you use your monitor to create or edit visual. About DisplayCAL. DisplayCAL (formerly known as dispcalGUI) is a display calibration and profiling solution with a focus on accuracy and versatility (in fact, the author is of the honest opinion it may be the most accurate and versatile ICC compatible display profiling solution available anywhere). At its core it relies on ArgyllCMS, an advanced open source color management system, to take. Thank you for downloading Calibrize. We hope you will enjoy the software. Back to home.
Windows
On Windows, open the Control Panel and search for 'calibrate.' Under Display, click on 'Calibrate display color.'
A window will open with the Display Color Calibration tool. It steps you through the following basic image settings: gamma, brightness and contrast, and color balance. For each, the tool will show you an example of what the ideal level should look like and then will provide a slider to make adjustments with a test image. For brightness and contrast, however, you will need to locate the controls; sliders aren't supplied.
When you have finished with your tweaks, the Display Color Calibration lets you compare your current settings with the previous calibration. Click Finish to move forward with your new calibration settings and Windows will make a pitch for you to turn on ClearType, which attempts to make text more readable. If you select this option, you will then jump through five quick test screens to fine tune ClearType for the clearest, crispest text.
Mac OS X
On a Mac, go to System Preferences > Display and click on the Color tab. Next, click the Calibrate button, which opens the Display Calibrator Assistant. It walks you through calibrating your display and then creates a calibrated color profile.
There is a box you can check for Expert Mode. If you leave this option unchecked, you will access only two settings: target gamma and white point. And, really, it's only one setting because target gamma -- a fancy term for 'contrast' -- in most cases should be left at the standard 2.2 setting. And in my experience, the white point setting didn't offer much of a range of options. The D50 warm setting was too yellow while the cool 9300 was too blue, and the D65 neutral white and Native settings were indistinguishable from one another.
So, let's go back and check the box for Expert Mode. Now, we can access five test patterns to tweak the native gamma -- or luminance -- of your display. Next, you have more options for the target gamma, but the Mac standard gamma of 2.2 is still recommended. Similarly, there are more options for the white point, which adjusts the overall color tint of the display. Again, unless you are engaging in particular graphics work that requires an odd setting, it's probably best to use the native white point. Lastly, Expert Mode lets you act as an administrator and choose whether to allow other user access to this calibration profile.
To finish up, give your profile a name and click Done. Your new profile will now be listed as an option on the Color tab of the Display option in System Preferences.
Editors' note: It's spring cleaning time! Week's three's theme: getting optimized. Check back every day this week to see how to get the most out of your devices and services. And be sure to return next week for more spring cleaning tips and tricks.
Table of contents
About DisplayCAL
DisplayCAL (formerly known as dispcalGUI) is a display calibration and profiling solution with a focus on accuracy and versatility (in fact, the author is of the honest opinion it may be the most accurate and versatile ICC compatible display profiling solution available anywhere). At its core it relies on ArgyllCMS, an advanced open source color management system, to take measurements, create calibrations and profiles, and for a variety of other advanced color related tasks.
Calibrate and characterize your display devices using one of many supported measurement instruments, with support for multi-display setups and a variety of available options for advanced users, such as verification and reporting functionality to evaluate ICC profiles and display devices, creating video 3D LUTs, as well as optional CIECAM02 gamut mapping to take into account varying viewing conditions. Other features include:
DisplayCAL is developed and maintained by Florian Höch, and would not be possible without ArgyllCMS, which is developed and maintained by Graeme W. Gill.
ScreenshotsDisplay & instrument settings Calibration settings Profiling settings 3D LUT settings Verification settings Testchart editor Display adjustment Profile information Calibration curves KDE5 Mac OS X Windows 10 Disclaimer
This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 3 of the License, or (at your option) any later version.
This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.
DisplayCAL is written in Python and uses the 3rd-party packages NumPy, wxPython (GUI[4] toolkit), Certifi, PyGObject or dbus-python for Linux (required for Wayland support with colord), as well as Python extensions for Windows, comtypes and the Python WMI module to provide Windows-specific functionality. Other minor dependencies include faulthandler, psutil, PyChromecast and pyglet (macOS/Windows) or libSDL2 (Linux). It makes extensive use of and depends on functionality provided by ArgyllCMS. The build system to create standalone executables additionally uses py2app on Mac OS X or py2exe on Windows. All of these software packages are © by their respective authors.
Get DisplayCAL
Please continue with the Quickstart Guide.
Quickstart guide
This short guide intends to get you up and running quickly, but if you run into a problem, please refer to the full prerequisites and installation sections.
System requirements and other prerequisitesGeneral system requirements
Hardware requirements
ArgyllCMS
To use DisplayCAL, you need to download and install ArgyllCMS (1.0 or newer).
Supported instruments
You need one of the supported instruments to make measurements. All instruments supported by ArgyllCMS are also supported by DisplayCAL. For display readings, these currently are:
Colorimeters
Spectrometers
If you've decided to buy a color instrument because ArgyllCMS supports it, please let the dealer and manufacturer know that “You bought it because ArgyllCMS supports it”—thanks.
Note that the i1 Display Pro and i1 Pro are very different instruments despite their naming similarities.
Also there are currently (2014-05-20) five instruments (or rather, packages) under the ColorMunki brand, two of which are spectrometers, and three are colorimeters (not all of them being recent offerings, but you should be able to find them used in case they are no longer sold new):
Color Calibration Software
Additional requirements for unattended calibration and profiling
When using a spectrometer that is supported by the unattended feature (see below), having to take the instrument off the screen to do a sensor self-calibration again after display calibration before starting the measurements for profiling may be avoided if the menu item “Allow skipping of spectrometer self-calibration” under the “Advanced” sub-menu in the “Options” menu is checked (colorimeter measurements are always unattended because they generally do not require a sensor calibration away from the screen, with the exception of the i1 Display 1).
Unattended calibration and profiling currently supports the following spectrometers in addition to most colorimeters:
Be aware you may still be forced to do a sensor calibration if the instrument requires it. Also, please look at the possible caveats.
Additional requirements for using the source code
You can skip this section if you downloaded a package, installer, ZIP archive or disk image of DisplayCAL for your operating system and do not want to run from source.
All platforms:
Linux:Windows:macOS:Additional requirements for compiling the C extension module
Normally you can skip this section as the source code contains pre-compiled versions of the C extension module that DisplayCAL uses.
Linux:
Mac OS X:
Windows:
Running directly from source
After satisfying all additional requirements for using the source code, you can simply run any of the included
.pyw files from a terminal, e.g. python2 DisplayCAL.pyw , or install the software so you can access it via your desktop's application menu with python2 setup.py install . Run python2 setup.py --help to view available options.
One-time setup instructions for source code checked out from SVN:
Run
python2 setup.py to create the version file so you don't see the update popup at launch.
If the pre-compiled extension module that is included in the sources does not work for you (in that case you'll notice that the movable measurement window's size does not closely match the size of the borderless window generated by ArgyllCMS during display measurements) or you want to re-build it unconditionally, run
python2 setup.py build_ext -i to re-build it from scratch (you need to satisfy the requirements for compiling the C extension module first).
InstallationInstrument driver installation under Windows
You only need to install the Argyll-specific driver if your measurement device is not a ColorMunki Display, i1 Display Pro, Huey, ColorHug, specbos, spectraval or K-10 (the latter two may require the FTDI virtual COM port driver instead).
To automatically install the Argyll-specific driver that is needed to use some instruments, launch DisplayCAL and select “Install ArgyllCMS instrument drivers..” from the “Tools” menu. Alternatively, follow the manual instructions below.
If you are using Windows 8, 8.1, or 10, you need to disable driver signature enforcement before you can install the driver. If Secure Boot is enabled in the UEFI[12] setup, you need to disable it first. Refer to your mainboard or firmware manual how to go about this. Usually entering the firmware setup requires holding the DEL key when the system starts booting.
Method 1: Disable driver signature enforcement temporarily
Best Free Color Calibration Software
Method 2: Disable driver signature enforcement permanently
To install the Argyll-specific driver that is needed to use some instruments, launch Windows' Device Manager and locate the instrument in the device list. It may be underneath one of the top level items. Right click on the instrument and select “Update Driver Software..”, then choose “Browse my computer for driver software”, “Let me pick from a list of device drivers on my computer”, “Have Disk..”, browse to the Argyll_VX.X.Xusb folder, open the ArgyllCMS.inf file, click OK, and finally confirm the Argyll driver for your instrument from the list.
To switch between the ArgyllCMS and vendor drivers, launch Windows' Device Manager and locate the instrument in the device list. It may be underneath one of the top level items. Right click on the instrument and select “Update Driver Software..”, then choose “Browse my computer for driver software”, “Let me pick from a list of device drivers on my computer” and finally select the desired driver for your instrument from the list.
Linux package (.deb/.rpm)
A lot of distributions allow easy installation of packages via the graphical desktop, i.e. by double-clicking the package file's icon. Please consult your distribution's documentation if you are unsure how to install packages.
If you cannot access your instrument, first try unplugging and reconnecting it, or a reboot. If that doesn't help, read “Installing ArgyllCMS on Linux: Setting up instrument access”.
Mac OS X
Use the Installer Package to install DisplayCAL to your “Applications” folder. Afterwards open the “DisplayCAL” folder in your “Applications” folder and drag DisplayCAL's icon to the dock if you want easy access.
If you want to use the HCFR colorimeter under Mac OS X, follow the instructions under “installing ArgyllCMS on Mac OS X” in the ArgyllCMS documentation.
Windows (Installer)
Launch the installer which will guide you trough the required setup steps.
If your measurement device is not a ColorMunki Display, i1 Display Pro, Huey, ColorHug, specbos, spectraval or K-10, you need to install an Argyll-specific driver (the specbos, spectraval and K-10 may require the FTDI virtual COM port driver instead). See “Instrument driver installation under Windows”.
Windows (ZIP archive)
Unpack and then simply run DisplayCAL from the created folder.
If your measurement device is not a ColorMunki Display, i1 Display Pro, Huey, ColorHug, specbos, spectraval or K-10, you need to install an Argyll-specific driver (the specbos, spectraval and K-10 may require the FTDI virtual COM port driver instead). See “Instrument driver installation under Windows”.
Source code (all platforms)
See the “Prerequisites” section to run directly from source.
Starting with DisplayCAL 0.2.5b, you can use standard distutils/setuptools commands with setup.py to build, install, and create packages.
sudo python setup.py install will compile the extension modules and do a standard installation. Run python setup.py --help or python setup.py --help-commands for more information. A few additional commands and options which are not part of distutils or setuptools (and thus do not appear in the help) are also available:
Additional setup commands
Additional setup options
Instrument-specific setup
If your measurement device is a i1 Display 2, i1 Display Pro, ColorMunki Display, DTP94, Spyder2/3/4/5, you'll want to import the colorimeter corrections that are part of the vendor software packages, which can be used to better match the instrument to a particular type of display. Note: The full range of measurement modes for the Spyder4/5 are also only available if they are imported from the Spyder4/5 software.
Choose “Import colorimeter corrections from other display profiling software..” from DisplayCAL's “Tools” menu.
If your measurement device is a Spyder2, you need to enable it to be able to use it with ArgyllCMS and DisplayCAL. Choose “Enable Spyder2 colorimeter..” from DisplayCAL's “Tools” menu.
Basic concept of display calibration and profiling
If you have previous experience, skip ahead. If you are new to display calibration, here is a quick outline of the basic concept.
First, the display behavior is measured and adjusted to meet user-definable target characteristics, like brightness, gamma and white point. This step is generally referred to as calibration. Calibration is done by adjusting the monitor controls, and the output of the graphics card (via calibration curves, also sometimes called video LUT[7] curves—please don't confuse these with LUT profiles, the differences are explained here) to get as close as possible to the chosen target.
To meet the user-defined target characteristics, it is generally advisable to get as far as possible by using the monitor controls, and only thereafter by manipulating the output of the video card via calibration curves, which are loaded into the video card gamma table, to get the best results.
Second, the calibrated displays response is measured and an ICC[5] profile describing it is created.
Optionally and for convenience purposes, the calibration is stored in the profile, but both still need to be used together to get correct results. This can lead to some ambiguity, because loading the calibration curves from the profile is generally the responsibility of a third party utility or the OS, while applications using the profile to do color transforms usually don't know or care about the calibration (they don't need to). Currently, the only OS that applies calibration curves out-of-the-box is Mac OS X (under Windows 7 or later you can enable it, but it's off by default and doesn't offer the same high precision as the DisplayCAL profile loader)—for other OS's, DisplayCAL takes care of creating an appropriate loader.
Even non-color-managed applications will benefit from a loaded calibration because it is stored in the graphics card—it is “global”. But the calibration alone will not yield accurate colors—only fully color-managed applications will make use of display profiles and the necessary color transforms.
Regrettably there are several image viewing and editing applications that only implement half-baked color management by not using the system's display profile (or any display profile at all), but an internal and often unchangeable “default” color space like sRGB, and sending output unaltered to the display after converting to that default colorspace. If the display's actual response is close to sRGB, you might get pleasing (albeit not accurate) results, but on displays which behave differently, for example wide-color-gamut displays, even mundane colors can get a strong tendency towards neon.
A note about colorimeters, displays and DisplayCAL
Colorimeters need a correction in hardware or software to obtain correct measurements from different types of displays (please also see “Wide Gamut Displays and Colorimeters” on the ArgyllCMS website for more information). The latter is supported when using ArgyllCMS >= 1.3.0, so if you own a display and colorimeter which has not been specifically tuned for this display (i.e. does not contain a correction in hardware), you can apply a correction that has been calculated from spectrometer measurements to help better measure such a screen.
You need a spectrometer in the first place to do the necessary measurements to create such a correction, or you may query DisplayCAL's Colorimeter Corrections Database, and there's also a list of contributed colorimeter correction files on the ArgyllCMS website--please note though that a matrix created for one particular instrument/display combination may not work well for different instances of the same combination because of display manufacturing variations and generally low inter-instrument agreement of most older colorimeters (with the exception of the DTP94), newer devices like the i1 Display Pro/ColorMunki Display seem to be less affected by this. Starting with DisplayCAL 0.6.8, you can also import generic corrections from some profiling softwares by choosing the corresponding item in the “Tools” menu.
If you buy a screen bundled with a colorimeter, the instrument may have been matched to the screen in some way already, so you may not need a software correction in that case.
Special note about the X-Rite i1 Display Pro, ColorMunki Display and Spyder4/5 colorimeters
These instruments greatly reduce the amount of work needed to match them to a display because they contain the spectral sensitivities of their filters in hardware, so only a spectrometer reading of the display is needed to create the correction (in contrast to matching other colorimeters to a display, which needs two readings: One with a spectrometer and one with the colorimeter).
That means anyone with a particular screen and a spectrometer can create a special Colorimeter Calibration Spectral Set ( .ccss ) file of that screen for use with those colorimeters, without needing to actually have access to the colorimeter itself.
Usage
Through the main window, you can choose your settings. When running calibration measurements, another window will guide you through the interactive part of display adjustment.
Settings file
Here, you can load a preset, or a calibration (
.cal ) or ICC profile (.icc / .icm ) file from a previous run. This will set options to those stored in the file. If the file contains only a subset of settings, the other options will automatically be reset to defaults (except the 3D LUT settings, which won't be reset if the settings file doesn't contain 3D LUT settings, and the verification settings which will never be reset automatically).
If a calibration file or profile is loaded in this way, its name will show up here to indicate that the settings reflect those in the file. Also, if a calibration is present it can be used as the base when “Just Profiling”.
The chosen settings file will stay selected as long as you do not change any of the calibration or profiling settings, with one exception: When a .cal file with the same base name as the settings file exists in the same directory, adjusting the quality and profiling controls will not cause unloading of the settings file. This allows you to use an existing calibration with new profiling settings for “Just Profiling”, or to update an existing calibration with different quality and/or profiling settings. If you change settings in other situations, the file will get unloaded (but current settings will be retained—unloading just happens to remind you that the settings no longer match those in the file), and current display profile's calibration curves will be restored (if present, otherwise they will reset to linear).
When a calibration file is selected, the “Update calibration” checkbox will become available, which takes less time than a calibration from scratch. If a ICC[5] profile is selected, and a calibration file with the same base name exists in the same directory, the profile will be updated with the new calibration. Ticking the “Update calibration” checkbox will gray out all options as well as the “Calibrate & profile” and “Just profile” buttons, only the quality level will be changeable.
Predefined settings (presets)
Starting with DisplayCAL v0.2.5b, predefined settings for several use cases are selectable in the settings dropdown. I strongly recommend to NOT view these presets as the solitary “correct” settings you absolutely should use unmodified if your use case matches their description. Rather view them as starting points, from where you can work towards your own, optimized (in terms of your requirements, hardware, surroundings, and personal preference) settings.
Why has a default gamma of 2.2 been chosen for some presets?
Many displays, be it CRT, LCD, Plasma or OLED, have a default response characteristic close to a gamma of approx. 2.2-2.4 (for CRTs, this is the actual native behaviour; and other technologies typically try to mimic CRTs). A target response curve for calibration that is reasonably close to the native response of a display should help to minimize calibration artifacts like banding, because the adjustments needed to the video card's gamma tables via calibration curves will not be as strong as if a target response farther away from the display's native response had been chosen.
Of course, you can and should change the calibration response curve to a value suitable for your own requirements. For example, you might have a display that offers hardware calibration or gamma controls, that has been internally calibrated/adjusted to a different response curve, or your display's response is simply not close to a gamma of 2.2 for other reasons. You can run “Report on uncalibrated display device” from the “Tools” menu to measure the approximated overall gamma among other info.
Tabs
The main user interface is divided into tabs, with each tab containing a sub-set of settings. Not all tabs may be available at any given time. Unavailable tabs will be grayed out.
Choosing the display to calibrate and the measurement device
After connecting the instrument, click the small icon with the swirling arrow in between the “Display device” and “Instrument” controls to detect connected display devices and instruments.
Choosing a display device
Directly connected displays will appear at the top of the list as entries in the form “Display Name/Model @ x, y, w, h” with x, y, w and h being virtual screen coordinates depending on resolution and DPI settings. Apart from those directly connected displays, a few additional options are also available:
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