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A brief explanation of Colour Management
Keith is often asked to give a quick explanation of colour management.
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This explanation was written after numerous conversations with people, discussing why they should look at colour management to improve their printing, whether for photos, or products in a catalogue. There are a lot of more detailed articles and books on what colour management is about, and we have links to some very well written ones at the end of this short piece. The What's New Page gives a quick overview of the hundreds of pages of articles and picture on this site. This page is part of the Articles section of our Info and Resources feature |
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?
Which red is red, and is it really red?
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.
So many reds to choose from...
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.
Contact details :
Northlight Images, 86 Harrow Road Leicester, Leicestershire, UK. LE3 0JW (Maps) Telephone +44 116 291 9092 You can e-mail us:
Colour management info 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. - 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. - 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. - 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. - Printer test images
- 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 and the web - why getting good colour on web sites is not as easy as you thought
- Adjusting your monitor 'by eye'
Not the best way, but better than nothing at all - Dual monitor profiling under Windows XP SP2 - A brief note on profiling and calibrating dual monitor systems under Windows XP SP2.
- Removing Adobe Gamma - Adobe Gamma is often installed by default on Windows PCs, this short note describes how to deactivate it.
- Improving Colour on the Mac
Equipment and software reviews
X-rite (ex GretagMacbeth)- 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 LT - review
Basic X-rite i1 spectrophotometer package for monitor calibration, light measurement and basic printer profiling. - i1 Design
A Spectrophotometer and software for monitor calibration, light measurement and basic printer profiling. - 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.
Sept. 2008 X-rite have updated the i1 (Eye One) 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*
*Requires Digital ColorChecker SG Chart - available separately.
Datacolor (aka ColorVision)
- Spyder3 Print - 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 monitor and projector profiling system with multiple monitor support and ambient light measurement.
- Spyder2express
The latest 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 (it also now supports vista). - 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
- 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. - GrafiLite
A review of the Ott Lite based print viewing lamp.
Other areas of our site that may be of interest...
NEW -- Create your own customised A3 size wall calendar from a choice of 90 of Keith's images. Choose your own images for your own custom printed calendar - 12 months starting any month of the year - many all new images not yet in our main gallery.
Digital Black and White. Keith was recently interviewed about digital black and white photography for a magazine article. We have an expanded version here covering some of his thoughts, techniques and tips for those thinking of trying black and white.
As well as our Commercial Photography services and Training there is a growing collection of photography Articles and Reviews on the site aimed at helping you get the best out of your own photography. We also have a growing collection of Photography related information and links that we hope you find useful.
New site features and some of Keith Cooper's latest work are always covered in the What's New page.
Visiting Leicester or wondering where it is? We have views from the Leicester traffic cameras.