Colour is More Than Spectral Data

You could be a professional, semi-professional, or just an enthusiastic digital photographer, or a graphic designer. Perhaps you're designing for the web as well as for print, or your photos find their way into glossy magazines as adverts or illustrations with articles. You're used to working with and in colour --or so you think.

Of course you know colour theory, and perhaps you even know what digital colour involves. But chances are that you don't know the finesses of what we call "colour management" --the (more or less) sure way to have a colour appear exactly the same (measurably) when displayed on a monitor or through a projector, printed with a photo inkjet printer on any type of paper or on a high-end Heidelberg printing press, or output to the web.

You might even not care. If you're a layout designer, for example, you may think you can say it's not your business to mind the RGBs and CMYKs of your files. You would be wrong in a sense that, if you don't care for the colour model, the colour space, and all those other colour management elements, the cost of your design could go through the roof because of colour inaccuracies later in the publishing workflow.

Commercial photographers find that layout designers often don't care enough in order to make sure their carefully crafted photos end up looking the way they intended them in the first place. But even photographers are not always savvy about colour management, and those who are often only know about "their" colour model (and working space) which is RGB, CMYK being the great unknown to them.

Colour is more than just colour management, of course. It's also about emotions, an atmosphere, harmonious design and even health (as in colour therapy). THINCK.com will try to be about all those aspects of colour (except for colour therapy --we're definitely not going to elaborate on that topic). So, if you're a designer or a photographer and want to learn more about colour and colour management, then read on.

How hard is it: Getting Accurate Colour Throughout a Digital Image or Design Workflow?

Colour is an important messenger. As a quality of light, it literally is present in everything we see. It conveys meaning and beauty. Colours can be used as signals and symbols and they are used as such by marketing people, designers, artists, and art photographers. In that sense, colour has been around for many hundreds of years.

Colour management on the other hand is of a much more recent date. Before the digital revolution in publishing and printing, almost every printer with a colour-capable printing press would have his own method of making sure the colours in the (physical) files he would have to print would match those of the original design.

Only when publishing became digital, did this way of working become totally unacceptable. There were no common frameworks, nothing that could serve as a standard (there were standards actually, but those didn't really say much about managing colours from one device to another). The International Colour Consortium (ICC) was the ideal industry group to develop a colour management system that would ensure a colour would look the same whether it would be shown on a monitor, or printed on a colour printer.

The ICC developed a clever system that was based on a number of concepts: the colour model, a colour working space, and colour profiles for devices. The working space is a range of colours --literally a space of colours-- that you will work in when designing or photo-editing. The colour profile defines the colour-related behaviour of a device. An interconnect system (the CMS or Colour Management System) makes sure that colour values are translated when you change devices.

When you display an image in the RGB colour model --in the AdobeRGB working space to be exact-- and you want this colour to look exactly as you see it on-screen when printed on your HP Photosmart Pro B9180, the colour engine of your PC (ColorSync for Mac OS users) will translate the colour data from the screen device to colour data that matches the colour as you see it on the printer. Inevitably, some differences will occur (in this example: the screen's colours look different from anything printed because a screen "radiates" light whereas paper absorbs it).

A word on THINCK.com

THINCK.com is published as an independent part of IT Enquirer, a web magazine on cross-media publishing. IT Enquirer and THINCK.com are published by Erik Vlietinck. Erik has written a number of articles on colour management and colour profiling, and reviewed colour management equipment and systems. Some of these can be read on IT Enquirer.