In the 1970's, the CIE went one step better and came up with a mathematical model of colour space called LAB - a standard providing a three dimensional view that is the most complete color model used conventionally to describe all the colors visible to the human eye.

 

 

 

 

Lab in all it's 3 dimensional glory

 

LAB provides a range of numbers ( eg: 255,255,0) that describe how a colour looks under certain lighting conditions, from a standard distance to a point on the retina of an eye, to the average person. And it defines colour values in a device independant manner - the colour is consistent colour regardless of the device producing it. Now let's look at this in context. The horseshoe is often used to show the range of gamut available to a colour space from Adobe 1998, sRGB to CYMK. Gamut shows how wide a colour space is in for any device. Monitors, printers, scanners and digital cameras have differing gamuts and render colours in different ways. So what happens when you combine all these devices and make the final print out? Usually an image that is totally off from what you expected. 

 

 

 

To combat this problem, in 1993, an organisation called the International Colour Consortium or ICC was created to make a set of colour standards. The idea was simple - to provide a point of reference to allow these devices to work in a consistent, accurate and managed environment. ICC profiles attached to the software of any device or compliant operating system allow the system wide communication of the ICC profiles between devices. The ICC profile can tell the operating system or software the correct colour space, ensuring the best possible colour rendering between the devices. Macintosh users have enjoyed ICC compliance for many years with the PC platform jumping on the bandwagon properly in Windows 2000 and XP.

 

Proper colour management profiles are the key to quality results from digital files.

 

Typical profiles would include: Monitor , Scanner , Camera, Printer.

 

Perhaps the first most important step is the accurate calibration of the monitor - the device that allows you to judge and correct images. Don't be fooled into thinking a software solution such as Adobe Gamma correction will do. For good consistent results you need proper hardware profiling equipment. Let's see if the Eye One can cure those ICC blues and take us on the road to colour management nirvana...

 

Gretag MacBeth Eye One Calibration

 Written instructions supplied with the package are very basic with just a few simple steps. The first indicates the installation of the software from the cd before plugging the colorimeter into a spare USB port. The software installs quickly and after connecting the device, Windows XP (also compatible with windows 98, ME, Windows 2000 and Mac OS 9.1 or higher - phew) recognizes the new hardware and completes the setup process. And that's the whole installation process and the end of the written instruction booklet.

 

It might have been nice if Gretag included a few pages on colour management and tips for getting the most out of the system to rounds things off. Good job they have an excellent web site that covers a whole range of colour topics for beginner to advance users along with a members only support section.

 

Running the Eye One software is a straightforward affair. A flash tutorial is available at every stage of the calibration process, should you need help, and a step by step approach makes the whole thing a breeze. To demonstrate how easy it is, here's a quick run down for profiling a monitor on a PC platform.   Before jumping right in to the good stuff, it's a good idea to make sure any current profile is removed from the system startup folder and the advanced colour management settings located within control panel display properties - color management. If you have photoshop installed make sure Adobe Gamma is disabled. This should prevent any conflicts with the new profile. Fire up the software, choose the device you would like to profile (in this case a monitor) and you should see a screen like this: