The basics of colour management

Colours in your computer are usually represented by three numbers that represent proportions of red, green and blue light.

When mixed, these will correspond to a particular colour we see.

This is based on the way our colour vision works and gives what are known as RGB values.

But what are these colours?

What does the 'red' number in an RGB value represent?

... the red of a London bus, or the red of a UK Telephone box?

Well, there are standards which define ways of measuring colours and can give absolute values and meaning to the numbers in a RGB value.

These numbers are completely independent of any device (screen or printer) that may be used to display the colours represented.

However, consider your computer monitor - does its version of red match up with a standard?

No, and what's more, if you have a second monitor, its red probably won't match the first one.

The red (or any other colour) produced by your monitor is said to be 'device dependant'. One 'R' value may produce one colour red on one monitor and a different version on another.

What about your printer? Here it's even more difficult, since you are trying to reproduce red from coloured inks, none of which is (usually) red.

How do I even know that my camera has captured the 'correct' colour red?

Colour management is all about trying to relate all these device dependant colours to standards in a consistent useful way.

It's about trying to make sure that the picture I took of the red bus looks correct on my screen, your screen, my printer and your printer -- and they all match (as best as they can) to the bus I saw in the street at the time.

Typically, things called 'icc profiles' provide the translation between what an actual physical device can do, and the standards.

Colour management helps you get colour right more often...

It can get a bit more complicated though :-)

If you're looking for calibrators or profiling kit then we have reviews of most of the currently available kit listed below, along with more detailed articles about colour management.

Colour management information on this site

General Colour Management

Why don't my prints match my screen?
A short article showing why there is more to getting your prints to match your screen, than just calibrating your monitor. It's the vital first step, but you do need to consider some other factors for best results.
Why are my prints too dark?
One of the more common printing problems we get asked about. Addresses some of the steps you can take to produce more consistent prints.
Choosing a working space
There are a number of popular choices for working colour space when editing images. Keith shows examples and discusses his personal choices for different applications. One size definitely does not fit all.
Room and office decoration and lighting for photo editing
Some information on what to consider when setting up a space to work on digital images and evaluate prints.
The very simple guide to 'what is colour mangement'.
Is the red in RGB the same as a London bus, or a UK Telephone box? A very short explanation of what colour management is, and why you use it.
Colour management introduction
Beware the colour management Tar Pit
Know what levels of colour management (and expense ;-) suit the needs of your work... A personal view from Keith covering some of the things it is good for, but also why you should be careful to understand why you are doing it in the first place.
Printer test images
Media settings and profiling for third party inks
Keith recently converted an Epson Stylus COLOR 1160 to third party inks. In describing the profiling of a this set-up with a third party glossy paper, he shows how that often neglected aspect of profiling -driver media settings- can make all the difference between a so-so print and one that he would be happy to send out as a sample to his commercial clients. Test images for media selection.
Adjusting your monitor 'by eye'
Not the best way, but better than nothing at all
Colour management and the web - why getting good colour on web sites is not as easy as you thought
Removing Adobe Gamma - Adobe Gamma is often installed by default on Windows PCs, this short note describes how to deactivate it.
Dual monitor profiling under Windows XP SP2 - A brief note on profiling and calibrating dual monitor systems under Windows XP SP2.
Camera Profiling for ACR with the DNG Profile Editor
Using a ColorChecker card, we've created custom camera profiles for the Ricoh GX200. Used for processing RAW camera files with Adobe Camera Raw. Applicable to any camera producing RAW files that can be opened in ACR.
Using the ColorMunki for black and white with QTR
A special version of our black and white test print for reading linearisation data for QTR
Using QTR and PrintFIX PRO for better black and white prints
By using the PrintFIX PRO to take readings from a greyscale test target, you can create luminance only icc profiles that can give a noticeable improvement to black and white print set-ups. It can even be used to improve the results from the likes of Epson's new 'advanced black and white' print settings.
Colour Management
Links to articles and sites we've found useful.
(Please do let us know if you find something useful that we've missed)

Equipment and software reviews

X-rite (ex GretagMacbeth)

ColorChecker Passport - test card for photography. Also allows DNG camera profiles to be built for the Adobe ACR raw converter
i1iSis OBA compensation - Optical brighteners can cause problems in profiling some papers. Article shows why, and reviews X-rite's approach to building corrected profiles for different lighting conditions with the iSis.
ColorMunki Printer profiling - A detailed review looking at the ColorMunki ICC printer profiling system from X-Rite. This expands on this particular aspect of our initial review of the ColorMunki. Covers making and optimising printer profiles, with notes on profile evaluation.
ColorMunki - an initial review of this printer/projector/monitor calibration/profiling device.
i1 Beamer - A software upgrade and hardware attachment device for using the X-rite i1 Pro spectrophotometer for digital projector profiling
i1 Display 2 - Monitor calibration and profiling device from GretagMacbeth - also allows ambient light measurement. (see also updated Pantone version)
i1 Match update - updated monitor calibration functionality
i1 LT (i1Basic) - review
Basic X-rite i1 spectrophotometer package for monitor calibration, light measurement and basic printer profiling.
i1 XTreme - review
Complete i1 profiling package, printers, cameras, projectors, scanners.
i1 Design
A Spectrophotometer and software for monitor calibration, light measurement and basic printer profiling.
Measuring ruler - update to measuring ruler for the i1 design.
i1 scanner profiling
Using the Eye One with a scan target to get better results form your film or flatbed scanner.
i1 Camera profiling with the SG colorchecker
i1 printer profiling
More advanced printer profiling with the Eye One.
i1 profile editing - The Eye One Match software from GretagMacbeth (now X-rite) now allows you to edit icc printer profiles. How easy is it to use, and what things should you consider before editing profiles.
The Eye-One iO automated scanning table - review - An automated solution to improving the quality and accuracy of target measurement for printer profiles when using the i1 (ex Eye One) spectrophotometer.
i1 iSis - advanced measuring device for printer profiling.
An automated whole chart reader for printer profiling test charts. A3 and A4 versions provide spectrophotometer readings for both UV and UV-Cut (filtered) measurements.

May 2010 X-Rite annouce new profiling software for Q4 2010

i1 Match and ProfileMaker Pro will be superseded by i1Profiler later in 2010. We have some notes and press info in the X-rite information section of the Northlight blog. For purchases after April 1st 2010 here will be free upgrades, along with other offers when the software is available.

Sept. 2008 X-Rite and the current i1 range

It now consists of two options. The functionality is the same as we have reviewed, but exactly what you get varies. As a result of this rationalisation, the i1Photo, i1Photo SG, i1Proof and i1XT have all been discontinued, and the i1 range now consists of:

The i1Basic - i1Pro measuring device with monitor profiling software
The new i1XTreme - professional monitor, RGB and CMYK printer, camera, scanner and projector profiling, plus profile editing

With the i1XTreme you can calibrate and profile:

Monitors - LCD, CRT and laptops
RGB output devices
CMYK output devices
Scanners
Digital projectors
Digital cameras*

Datacolor (aka ColorVision)

Spyder3Elite V4.0 - Review of the improved and updated software for the Spyder 3 elite - Monitor and Projector calibration.
Spyder3express - review of Datacolor's basic calibration equipment and software
Spyder3Print SR - Full review of the latest printer profiling system from Datacolor. Updated spectrocolorimeter allows for strip and patch reading.
Spyder3Print - printer profiling package for creating icc printer profiles. Allows considerable optimisation of profile qualities, including black and white.
Spyder3Pro - monitor profiling with multiple monitor support and ambient light measurement.
Spyder3elite - review of the comprehensive monitor and projector profiling system with multiple monitor support and ambient light measurement.
Spyder2express - entry level monitor profiling system from ColorVision for Macs and PCs.
A review of the Spyder 2 pro monitor calibration system.
Projector profiling with the Spyder 2 Pro.
Spyder2PRO Ambient light measurement
The Spyder2PRO now allows you to measure your ambient room lighting conditions before deciding on monitor calibration settings.
PrintFIX PRO
A considerable upgrade to the PrintFIX. The new version uses a Spectrocolorimeter to let you create printer icc profiles (Not sold directly any more - you can ugrade the software for free to Spyder3 Print)
Updated PrintFIX PRO - better colour printing and B/W too...
PrintFIX PLUS
The software only version of PrintFIX PRO that allows you to create icc profiles without your own patch reader.
The original PrintFIX review
Printer profiling system (not sold directly any more)

Pantone

Pantone Eye One Display LT - monitor profiling. The mid range monitor profiling solution in the trio from Pantone. The measuring device is an Eye One Display LT from GretagMacbeth, and uses the Eye One Match software.
Pantone Eye One Display 2 - monitor profiling. The measuring device is an Eye One Display 2 from GretagMacbeth, and uses the Eye One Match software. This review has additional information to that in our original GretagMacbeth Eye One Display 2 review, and compares features between the Display 2, Display LT and Huey.
Pantone Huey Pro - review
Dual monitor support and and improved set of options compared to the basic huey.
Pantone Huey - review
The Huey is a new and relatively inexpensive addition to the monitor profiling market. Keith looks at how it performs, including its novel capacity to modify your monitor setup in response to changing room lighting.

Others

Desktop Print Viewer - PDV-3e - A review of the GTI print viewer, showing why having a well defined print viewing solution helps with print evaluation and soft proofing. Good lighting is a key factor in print consistency and prints looking more like you see on your monitor.
GrafiLite
A review of the Ott Lite based print viewing lamp.
ColorEyes Display Pro
Monitor profiling software that works with a variety of measurement devices.
Kodak Professional Colour Management check up kit - review
Print Profiler - review
An i1 based print and monitor profiling system from Colour Confidence.
Print Profiler - update
An improved version of the Print Profiler package.

Explore our site... Digital Black and White photography and printing - some of Keiths thoughts, techniques and tips for those interested in a digital approach to black and white. We've lots of original Photography Articles and Photography Reviews on the site to help anyone interested in photography. New site content appears on the What's New page.

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