I liked his following opinion of colour-handling…though it is questionable in some ways: ‘good colouring is comparable to good cooking. Even a good cooking recipe demands tasting and repeated tasting while it is being followed. And the best tasting still depends on a cook with taste.’ It’s definitely true that colour should be revisited/manually controlled – as the following examples will prove. Consistency in colour values, for instance, does not always equal consistency in colour to the eye (in other words, the same colour can appear different due to a variety of reasons, like light). In many circumstances, if the creator wants, say, two pieces of type to appear the same colour visually, it may be necessary to make them slightly different colours (if, say, their backgrounds are of different colours).
Here are a few interesting examples of colour interaction I’ve read about so far:
In the second image below (click on it for a proper view), there is a black rectangle with a grey centre square, and a white rectangle with a grey centre square. This is an example of making two different colours appear the same. The grey squares are repeated below the image, side-by-side. See the difference?
Similarly, (and excuse the imperfection of this one, as it was my own attempt and not a copy from the book), in the third image we see a bright pink rectangle and pale purple rectangle, each with an orange centre square. The orange appears the same colour in each if you gaze at the centre of the image. For clarity, the orange squares are repeated below, and the difference is again clear.
Then there is the ability of colours to make one colour look like two. The last pair of images demonstrate this – two rectangles, one purple, the other brown, appear to have centre squares whose hue equals that of the opposite large rectangle. Brown with purple square, purple with brown square. In reality, though, the small squares are the same colour, as repeated underneath the image.
The main point behind all this is that influencing colours (dominating colours/colours with the largest area or presence) will SUBTRACT their own hue from those colours that they influence. Put a certain green shape inside a large yellow area, for instance, and that green will lose some of the yellow to its appearance…thus becoming more blue. Or, simply, a black background makes a colour lighter (it loses its darkness) as a white makes colour darker.
So?? Well, for typographers, this lesson should be an important one. If the colour of your type always needs to be the same colour in a particular publication, it is only the visual level of colour that matters to the audience – so you should put trust in your own eyes and adjust the type colour ever so slightly to allow for backgrounds of strong colour-influence. As Albers would say, stop cooking and have a taste now and then.