6 Colour Order Systems
Definitions
colour order system (CIE)
"arrangement of samples according to a set of principles for the ordering and denotation of their colour, usually according to defined scales. NOTE A colour order system is usually exemplified by a set of physical samples, sometimes known as a colour atlas. This facilitates the communication of colour but is not a prerequisite for defining a colour order system".
colour atlas (CIE)
"collection of colour samples arranged and identified according to specified rules".
colour space (CIE)
"geometric representation of colour in space, usually of 3 dimensions".
In an alternative usage found particularly in the literature of Adobe Inc., the term color space is restricted to what the CIE calls a colorimetric colour space, and non-colorimetric colour spaces are referred to as color models.
colorimetric colour space (CIE)
"colour space defined by 3 colorimetric coordinates. NOTE CIE XYZ tristimulus values are colorimetric coordinates, as are RGB values that have an exact and invertible mathematical relationship to CIE XYZ tristimulus values". For definitions of the CIE colorimetric colour spaces see here.
Overviews
Color museum (Narciso Silvestrini and Ernst Peter Fischer):
Major summary of colour classification systems from antiquity to the present day.
ColorAcademy - Classification (Don Pavey and Roy Osborne)
Linked pages describe systems including CIE, Munsell, NCS, Ostwald, Pantone and the British Standards Institution. (Website currently accessible only via archive.org Wayback Machine).
CIE Colorimetry
A beginner’s guide to (CIE) colorimetry (Chandler Abraham)
How the CIE 1931 RGB Color Matching Functions Were Developed from the Initial Color Matching Experiments (Yuhao Zhu, @yzhu88)
Interactive Tutorials on Color Science Basics (Yuhao Zhu, @yzhu88)
A set of interactive tutorials in the form of Web apps that help understand basic concepts in color science originally developed for the Mobile Visual Computing course taught at University of Rochester by Yuhao Zhu.
Color vision (Craig Blackwell)
https://www.youtube.com/watch?v=82ItpxqPP4I (Color Vision 2: Color Matching)
https://www.youtube.com/watch?v=KDiTxWcD3ZE (Color Vision 3: Color Map)
Introduction to color theory (Mark Levoy, Katie Dektar)
https://graphics.stanford.edu/courses/cs178/applets/locus.html (excellent Flash apps, no longer working)
Emulating the Wright-Guild experiment (Edgardo García. MSEng, Buenos Aires University)
Principles of light and color measurement (Radiant Vision Systems, 2018)
Useful color data (Munsell Color Science Lab, RIT)
CIE convertor (Luxalight)
Converts wavelength or color temperature to CIE XYZ and shows colour on screen
Color Converter (Robin Myers)
https://web.archive.org/web/20160331060152/http://rmimaging.com/Color_Converter_2.3.zip (Windows/Mac)
A utility program for converting colors between XYZ, xyY, Lab, LCH(ab), Luv, LCH(uv) color spaces. You can set it to convert with over a dozen white point settings, including your own custom white points.
CIECAM02 Plug-In (Cliff Rames)
Interactive exploration of the CIECAM02 model.
LED ColorCalculator (Osram)
"The ColorCalculator software is a standalone program that allows designers to estimate the photometric performance of color mixing schemes. Designers can mix standard LEDs and calculate photometry of the resultant light. An optimization function is also available to adjust a design to user specified photometry target".
https://www.osram.us/cb/tools-and-resources/applications/led-colorcalculator/index.jsp
Handprint (Bruce MacEvoy)
https://www.handprint.com/HP/WCL/color6.html#colorimetry (colorimetry)
https://www.handprint.com/HP/WCL/color7.html (modern color models)
CIELAB & CAM02 color picker (Bastien Dejean)
Visualizing the XYZ color space (Sony)
Outstanding video of CIE XYZ in relation to other colour spaces
The CIELAB lecture (John Seymour)
Digital Colour Specification and Spaces
For discussion of software that uses these spaces and topics such as colour management, please see next section.
Color topics for programmers (Peter Occil)
Color spaces (Bartosz Ciechanowski)
Article incorporates excellent interactive demonstrations
Gamma FAQ (Charles Poynton)
Color FAQ (Charles Poynton)
Introduction to video color spaces (Charles Poynton)
The representation of color metrics and mappings in perceptual color space (Stephen Boker).
The color guide and glossary (Xrite).
Light and color: an introduction (Norman Koren): Relatively simple introduction to colour spaces for digital photographers/artists.
Graphics short course I: color theory and 2D image representation.
https://web.archive.org/web/20170111093014/http://viz.aset.psu.edu/gho/sem_notes/color_2d/index.html
Color: from hexcodes to eyeballs (Jamie Wong)
Mostly very good (but should have looked up what wavelengths a lemon reflects!).
Exploring color theory with Blender (Mark Meyer)
Visual representation of color names in different color spaces (David A., Codepen)
A perceptual color space for image processing (Björn Ottosson)
Color playground (Alexey Ardov) @ardovalexey
Interactive display of very up-to-date range of colour spaces.
See also Online and Downloadable Programs below.
Munsell System
Munsell.com (X-rite)
https://munsell.com/about-munsell-color/how-color-notation-works/
Blog with many articles relating to the Munsell system (not very active lately).
The dimensions of colour (David Briggs)
http://www.huevaluechroma.com/011.php (overview)
http://www.huevaluechroma.com/013.php (lightness)
Munsell color system (Bruce MacEvoy)
Colour Mixing Tools (Zsolt Kovacs-Vajna)
Suite of free programs comprising:
Color2Drop (a program to convert RGB, Lab or Munsell HVC color coordinates into paint mixing recipes)
Drop2Color (a program to visualize the color of mixed paint recipes)
RS2Color (a program to visualize the color of reflectance spectra)
ChromaMagic (Michele Clamp)
Upload an image to find the nearest Munsell notation of a selected pixel.
https://micheleclamp.com/the-munsell-color-system/ (clear introduction to the Munsell system)
ColorWell (John Morfis)
The Munsell Explorer find artists' oil paints by their rated Munsell notations and another tool generates shading series for any Munsell notation.
Color Translator & Analyzer (Babelcolor)
"CT&A (Color Translator & Analyzer) is a collection of tools specifically designed for the measurement, conversion, and analysis of individual colors or small batches of colors". Commercial software, but some operations work in demo mode, notably including bidirectional conversion between various RGB spaces and Munsell.
The digital Munsell (Gernot Hoffman)
A pdf of the colours of the Munsell Book of Color glossy edition,with CIE L*a*b* and sRGB conversions.
Munsell Conversion Software (WallkillColor): Features:
http://wallkillcolor.com/Munsell20/index.htm (Windows, rentware)
Converts Munsell Notation to XYZ, L*a*b*, RGB, CMYK
Converts RGB to XYZ, L*a*b*, Munsell Notation - CIELAB correction for dark colors added
Displays Color on screen
Print pages to color Printer
Munsell Book of Color
Value Page that shows all Hues and Chromas for a constant value
Color Tolerance Page that displays a Munsell color with pairs of
lighter/darker, redder/greener and Yellower/Bluer
Image Analysis - Load a JPG picture and select spots to display Munsell Notation
Charting color from the eye of the beholder (Landa and Fairchild): Reprint of American Scientist article on Munsell and the Munsell system.
Munsell renotation data (Munsell Color Science Lab, RIT)
Conversions between the Munsell and sRGB colour systems (Paul Centore)
Virtual Munsell Color Wheel (Andrew Werth)
Munsell Color Palette (Andrew Geng)
See also under "Hue, Lightness and Chroma" onthe page on Basic Colour Attributes.
sRGB Centroids for the ISCC-NBS Colour System (Paul Centore)
See also Virtual Atlas (VCS Consulting) below.
Natural Colour System (NCS)
NCS (Scandinavian Natural Colour System)
NCS in five steps (NCS)
NCS Navigator Freemium (NCS)
Swedish Natural Color System (Bruce MacEvoy)
NCS swatches for Adobe CS/CC
See also Virtual Atlas (VCS Consulting) below.
Other Systems
Optical Society of America Uniform Color Scales (OSA-UCS)
See also Virtual Atlas (VCS Consulting) below.
Hungarian Coloroid Colour System
See also Virtual Atlas (VCS Consulting) below.
Online and Downloadable Programs
See also "Online/downloadable programs" under Colour Vision Science.
Virtual Atlas (VCS Consulting)
"This free web application (IE, Safari and Chrome compatible) provides virtual colour atlases for the Colorcurve, Coloroid, DIN-6164, Munsell, NCS, OSA-UCS, and Swiss Colour Atlas 2541 colour order systems and for the BS:5252, RAL-840HR, and RAL-841GL colour ranges. In addition, the application supports spectral curve calculation, colour difference calculation, colour comparison, and colour notation conversion. Each colour atlas can be viewed in a range of different planes, for example Munsell can be viewed as planes of constant hue, value, or chroma, and each plane can be magnified up to 800% displaying calculated intermediate colours not present in the actual atlas."
Color Atlas (Harald Brendel)
Interactive atlas displaying and exporting adjustable vertical slices through CIE L*a*b*, CIE L*u*v*, CIECAM 02, IPT (Ebner and Fairchild, 1998), YCbCr and HSV.
Color calculators and spreadsheets (Bruce Lindbloom).
Select "Calc", "Info" or "Math" at the top of the page for various useful features including:
CIE Color Calculator: Converts among most of the CIE color models (XYZ, xyY, Lab, LCH(ab), Luv, and LCH(uv)), as well as providing correlated color temperature and standard RGB conversions.
Color Difference Calculator: Computes color differences using several different methods (Delta E, CIE94, CMC).
Spectral Calculator Spreadsheets: Calculates colorimetry, densitometry and RGB values from your spectral data.
ColorChecker RGB Summaries, Spreadsheets and Lab TIFF File: You will find three things on this page, a) summaries of the ColorChecker colors, expressed in each of many standard RGB color spaces, b) spreadsheets that allow you to findhich RGB color space is closest to your RGB values, and c) a computer generated Lab TIFF file of the ColorChecker.
Dot Gain from Lab or Profile: Two spreadsheets which calculate dot gain from Lab measurements, also allowing you to measure the dot gain of a CMYK ICC printer profile.
ColorChecker Calculator: Performs many spectral calculations on the 24 colors of the ColorChecker chart.
Chromatic Adaptation Calculator: Converts colors between reference whites using different chromatic adaptation algorithms.
Color Difference Calculator.
Formerly available features not currently on site (2020) include; Companding Calculator: Converts among luminance, CIE L*, density and gamma. Includes both a numeric calculator and a graphical display. CIE Spectral Display: Calculates and displays many useful CIE functions, such as the Standard Observers, the Standard Illuminants and blackbody radiators. Levels Calculator: See how you lose levels when you pass data through curves. Munsell Display Calculator: Displays the Munsell color set (2734 colors) in xyY, Lab and Luv. This is a useful tool for evaluating uniform perceptual color spaces. Also included is an explanation of the infamous "blue turns purple" problem often seen with printer profiles. Dot Gain Calculator: Performs the standard Murray-Davies dot gain equation to your density measurements.
Color Inspector 3D
http://home.htw-berlin.de/~barthel/ImageJ/ColorInspector/help.htm
https://imagej.net/Color_Inspector_3D (Color Inspector 3D plugin for ImageJ)
Standalone program and plugin for interactive visualization of image data in various color spaces. Very highly recommended.
Artists' Helper (Robert Burrage)
Among other uses, displays image colours in various colour spaces. Less intuitive to use than Color Inspector 3D but output is much more aesthetically pleasing.
Convert color data into different standards and color spaces (EasyRGB)
Interconvert sRGB <> sRGB 0-1.0 <> RGB Adobe 98 <> HSL <> HSV <> HSI <> CMY <> CMYK <> CMYK <> XYZ <> Yxy <> L*ab <> L*Ch(ab) <> L*uv <> L*Ch(uv) <> HunterLab and to match color data to color cards, paint lines, inks, fandecks, standards and other real world products and references.
Leonardo (Nate Baldwin)
Image Color Summarizer (Martin Krzywinski)
Other free online colour tools by the author include colorconvert which converts colors between color spaces, white points and RGB working spaces, and colorsnap , to find specific colors in an image or snap colors to a set of reference colors.
KGamut2 gamut tool (Cristian Romero)
Colorimeter (Android app)
Color Analysis (Android app)
Color Extractor (Android app)
Color Sliderule (Axiphos)
"This freeware package performs conversion of color data between different expressions for a given illuminant and observer, including also whiteness data. Conversions are possible between (Rx,Ry,Rz), (X,Y,Z), (Y,x,y), CIE-L*a*b*, Hunter-Lab, RGB, sRGB, Whiteness CIE and dominant wavelength and vice versa. Whiteness equations include whiteness indices after CIE, Ganz-Griesser (nominal parameters), Uchida, Berger, Stensby, Hunter, ASTM, Croes, Taube, Stephanson and Harrison; also yellowness index can be calculated."
Color conversions (Per Bang)
RGB <> Hexdecimal <> CMYK <> HSV <> HSL <> CIE-L*ab <> XYZ + Munsell, NCS, Pantone, RAL Classic etc.
Working with color
RGB <> HSB <> HSL<> CMYK(simple) <> CIE L*a*b* <>HSL <> Hex
Introduction to color (Eugene Vishnevsky):
Online Java applets explaining colour spaces.
Color Selector (Josiah Reynolds)
http://www.archive.org/download/tucows_304878_Color_Selector/cs3.zip (Windows; direct download)
"This program provides dynamically colored sliders supporting four color formats including RGB, HSL, HSB/HSV and CMY. It also has a color picker with zoom and area sampling, format converter, palette tool, seven built-in export formats, customizable formatting options including four built-in ones, and scripting support for VBScript and JScript, allowing you to replace export formats with anything you want".
Colorizer
"Color picker, calculator and generator with high precision and contrast test. Converts also RGB, HEX, HSL, HSV/HSB, CMYK and CIE-LAB colors and lots of other formats".
Color Converter
"Select a color space and enter your values for accurately convert your selection to Rgb, Cmy, Cmyk, Hsl, Xyz, Lab, Lch and Yxy".
CMM Color Engine (Little CMS)
"Open source small-footprint color management engine, with special focus on accuracy and speed. It fully supports all kind of V2 and V4 profiles, including abstract, devicelink and named color profiles. Free under MIT License".
Site also hosts commercial software including Color Translator, a "tool for color conversion on TIFF, JPEG, PNG, OpenEXR and PDF files. Batch conversion on file lists or hot-folders. It can deal with RGB, CMYK, Lab, black-preservation, smart intents, abstract profile adjustment chains, linear light color spaces and many, many more. Demo version works for free on files under 60K".
RGB colorspace transformation matrix and chromatically adapted primaries (color-science.org)
Color space conversions (github.com/colorjs/ )
Interconversion of 18 colour spaces
3D Gamut Viewer (PerfX )
HCL Wizard
Includes Palette Creator, Deficiency Emulator and Color picker online apps