‘Colour theory’ tells us how different combinations of colours will look, and how they will work together with other colours. The best way to understand it is by using colour wheels, which show it graphically.
The family tree of colours
Many colours can be formed from mixing other colours. There are only three original colours which cannot be created from any mixture of other colours. They are the primary colours. They are the colours from which every other colour ultimately derives. These primary colours are red, yellow and blue. That is the first wheel you see above.
Next, there are the colours which can be created by mixing primary colours together. They are the secondary colours. These secondary colours are green, orange, and purple. That is the second wheel you see above, which shows the three primary colours and – between each of them – the secondary colour formed by mixing those two primary colours.
Finally, there are colours which can be created by mixing a primary colour with a secondary colour. In colour theory, each such colour is given a name which is a combination of their parents. For example, red-orange is a mixture of the primary colour red and the secondary colour orange. These tertiary colours are yellow-orange, red-orange, red-purple, blue-purple, blue-green, and yellow-green. These are shown on the third wheel above, side-by side with their parent primary and secondary colour parents.
Displaying the colours graphically in a wheel means you can see a colour and also which other colour is exactly opposite it on the other side of the wheel. The other colour is its opposite. Opposite colours tend to neutralise each other. If there is too much of one colour, it can be reduced by adding some of its opposite colour. For example, if there is too much red, you can add some green – the opposite colour on the wheel.
An interesting example of this in practice is the Wimbledon official logo, which uses purple. The reason for that choice is that purple is almost exactly opposite green on the colour wheel. Purple stands out perfectly against the green of the tennis courts.
Warm and cool colours
Another useful visual aspect of the colour wheel is that half of it is shown as warm, and the other half as cool. This ties in with the idea of warm and cool undertones. There is no hard and fast agreement as to the exact dividing points, but you can see roughly which is which by looking at the wheel.
Hues, tints, shades, and tones
Colours in the world are a lot more complex and varied than the colours shown on the wheel. These are the additional factors.
The ‘hue’ of a colour is the primary or secondary colour which is its main component. The hue can only be red, yellow, blue, green, orange, or purple. In normal life, people use ‘hue’ interchangeably with ‘colour’, but in professional use it means the original source colour. Black, white and grey are not hues.
Add white to any colour and you have a ‘tint’. There is no change in colour at all. The colour simply gets paler, and it may seem brighter. It doesn’t matter whether you end up with a colour with a drop of white, or a whole lot of white and a drop of colour. It is still a tint of the colour.
A ‘shade’ is the exact opposite of a tint. A shade is any colour to which black has been added. As with a tint, It doesn’t matter whether you end up with a colour with a drop of black, or a lot of black with the merest drop of colour. It is still a shade of the colour.
A ‘tone’ is any hue or mixture of colours with only grey added. Since gray is a mixture of black and white, a tone a combination of the effects of a tint and a shade. Gray tends to dull a colour.
What has any of this got to do with your search for the perfect eyebrow colour? You aren’t planning to use purple or magenta, and you don’t care what is mixed with them.
You will be operating in the tiny segment of the wheel that is ‘brown. But even there, brown pigment will need to be lightened, darkened, and have warmth or coolness added to it. You might as well understand the principles, so you understand what your technician is talking about when she is trying to arrive at the best colour for you. It is the most important decision, after all.