About complementary colours and colour wheels
- Complementary colours are always opposite one another on a colour wheel.
- The complementary colour of a primary colour is always a secondary colour on a colour wheel.
- The pairs of primary and secondary colours that produce complementary colours depend on the colour model:
- When mixing light (using an additive colour model) the pairs are red-cyan, green-magenta and blue-yellow
- When mixing pigments (using a subtractive colour model) the pairs are red-green, yellow-purple and blue-orange
- In the case of digital printing (using a subtractive colour model) the pairs are cyan-red, magenta-green and yellow-blue
- Whilst the secondary colours in a subtractive RYB colour wheel are green, purple and orange, mixing pigments (eg. paints or inks) is a complicated business.
- Combinations of two complementary colours of light at full intensity produces white.
Complementary colours and the the RGB colour model
- When using the RGB colour model, the primary/secondary pairs of complementary colours are red-cyan, green-magenta and blue-yellow.
- Combining the wavelengths corresponding with all three RGB primary colours produces the impression of white for a human observer.
- When working with the RGB colour model the secondary colour that pairs with any primary colour is produced by mixing the other two primaries together.