Learn from the masters
Benefit from the knowledge garnered by thousands of fine artists through the ages: add depth and impact to your design through the clever use of colour. All colours have a bias towards temperature and are commonly described as warm or cool. To the human eye, ‘hot’ colours, such as reds and yellows, appear to advance while ‘cooler ’ blue and green hues recede. A mix of warm and cool colours can therefore be used to draw attention to a specific area of your design or to suggest depth in your image.

Colour and meaning
All colour comes loaded with multiple meanings – this should have a significant impact on your creative work. In Western symbolism, red indicates aggression, strength, passion, blood, anger and optimism, while yellow has connotations of cowardice, caution, fear, brightness and warmth. Beyond these obvious links, colours have different meaning in different cultures – something to bear in mind when working with international clients. Red means conservatism in US politics, but socialism in UK politics, and yellow is the colour of mourning in Egypt but means courage in Japan. Learn more about colour meaning at http://en.wikipedia.org/wiki/Color_psychology.

Colour effects
Aside from evoking cultural meaning and symbolism, colour usage can have physical effects on the viewer – which are worth considering, as they can enhance or detract from the core message of your design. Red can increase the pulse rate and blood pressure in a view and increase appetite, making it good for restaurant design. Children are naturally drawn to red. Yellow, on the other hand, has been shown to cause distress in babies, and make elderly people more prone to anger. However, yellow also enhances concentration and speeds up the metabolism. Discover more at www.colour-affects.co.uk.

Take care with body text
Using colour with text for printed work demands special consideration, specially for fine serif faces or elements such as keylines. The general rule is to avoid using tints to colour fine text, especially in cyan, yellow or magenta, as the text can end up looking very grainy with low tint values (such as 15 per cent or less). Similarly, white text on a lightly tinted background will roughen its edges, and if the printed project is misaligned, you’ll get significant mis-registration effects. The best bet is to stick with very saturated colours for body text, or avoid them altogether.

Colour spaces
As colour projects move between devices (from scanner to screen to print, for example), colour values are often mapped to a device’s colour space, such as to the RGB values of a monitor or the CMYK values of a commercial printer. All colour conversion maps to a colour gamut called L*a*b, where ‘L’ is the lightness from black to white, ‘a’ are hue values from red to green, and ‘b’ the hue values from blue to yellow. It’s a complex system, but it does offer a wide gamut – or values – of colours than CMYK or RGB, allowing you to more accurately tune your colour values. An interactive demonstration can be found at www.cs.rit.edu/~ncs/color/a_spaces.html

Understand rendering intents
When outputting colour work to a printer, you may come across options to alter rendering intents. These are a series of rules that dictate how colours are converted – there are four intents: absolute colourmetric, relative colourmetric, perceptual, and saturation rendering. Absolute colourmetric maintains colour accuracy, and is best used when proofing on a non-neutral substrate. Relative colourmetric rendering is best for moving a CMYK image from one device to another, as it ensures that colours are keep as intact as possible. Perceptual rendering is best avoided for proofing, but is great for outputting RGB as it best reproduces how our eyes see colour and works best for photos. Saturation rendering can also be avoided for general work, as it retains colour saturation information at the expense of brightness and hue. It can be used for graphics printing, such as business cards.

Spot the difference
If you’re using spot inks in your design, then adding a black to the ink colour boosts it by not just creating tints, but adds variety by adding in black tints as well. You can then vary the saturation and lightness of the spot colour. You can also mix spot colours by creating half-tone mixes between them – so don’t be limited when using spot colours in print.

Colour me last
Working with images in Photoshop is a destructive process – it eliminates values from the original image. As you edit an image, you increasingly destroy it, and that includes any colour adjustments, including layers and colour mode. It’s best to leave all colour work to as late as possible in the creative workflow so you are working with as intact an original image as possible.

Get it right in Photoshop
Colour settings can be complex in Photoshop, but with a few minutes’ work, your colour output can improve immeasurably. Choose Edit > Colour Settings and check the Advanced Mode box. Here, set RGB as Adobe RGB (1998) which handles a wide range of colours, or choose sRGB if you’re only working with images destined for the Web or screen-based media. Under the CMYK section, choose your printed destination (such as Euroscale Coated v2) and set Gray to a Dot Gain of 15 per cent for output in Europe. In the US, you’d set it to 20 per cent. Repeat for the Spot pop-up menu. Next, under the Colour Management Policies, choose Preserve Embedded Profiles. Ensure that the Conversion Engine is set to Adobe (ACE), and choose either relative colourmetric intent (for CMYK work) or Perceptual (for RGB output to print, such as photos). Finally, ensure Use Dither and Black Point Compensation are ticked, and save your settings.

Beware non-PostScript printers
When outputting your colour creation based on the above tips, be warned that most home and small studio printers are non-PostScript devices that usually do their best to oversaturate your images and mess up your work. To ensure accurate proofs from a non-PostScript printer, make sure you turn off options such as ‘Enhanced prints’ or set the ‘Quality’ option to ‘none’. If available, choose ‘Application defined colours’ from any colour management options to ensure a more accurate proof.

Illustration: Johann