7. Colour Interactions

To continue how afterimages modify our perception, let’s have a look at the following plate.

Around the violet rectangle we feel a thin red-violet border. The reddish afterimage of the green is blended optically with the violet to create this red-violet illusion. If we place the same violet rectangle against a gray background, the achromatic gray influences only the value and not the hue of the violet rectangle, which loses its former reddish halo, appearing darker, more saturated, more blue-violet.

Lets make the same experiment with two coloured backgrounds:

The violet rectangle against the red-orange background appears lighter and a little bluer (bluish afterimage) than it does against the pale green background (reddish afterimage).

You see a small note under the plates: Josef Albers: Interaction of color

This wonderful and very unorthodox book on colour theory is aviable as an app for iPads. (The basic theory is free, but if you want to play and experiment, there is a charge of 10$ for the app.)

Also from this book is the reversal of the examples above. In chapter VII, 2 different colors looks alike, Albers creates plates where two colours placed in different backgrounds looks identical. On closer examination they turn into two different ones, like the ones below.

These examples above can sensitize your colour perception by doing this two exercises several times over.

1.

One colour appears as two

Concentrate on trying to alter the value of the same colour by using different backgrounds. First work with grays – it’s easier – than use different hues.

Try to alter the hue of a single colour - keep the values closed to each other.

This one is a very important exercise: try to create glowing and dull sensation with the same colour. Using saturation right can cheer up your quilting, especially if you use commercial fabrics. They tend to be dull but in a right surroundings they can be perceived as glowing ones.

If you’re ready to go further:

Try to create the impression of altered hue, value and saturation within one exercise.

The most difficult will be Albers’ exercise VII: try to make two different colour appear as one.

2.

This exercise could be regarded as a combination of the part-exercises above:

Use at least 6-8 colours, each of them twice (no more). Try to create a design to demonstrate color interaction: arrange your colours so that the same colours appear different.