HSB colour model & saturation

About the HSB colour model and saturation

The HSB colour model, like the RGB colour model, is an additive colour model used to mix light.

  • The RGB and HSB colour models differ in the way colours are represented and handled in software and apps.
  • Both the HSB and RGB colour models involve mixing red, green, and blue light to create various colours.
  • HSB is popular due to its intuitive colour selection and adjustment in applications like Adobe Creative Cloud for design, photography, or web development.
  • The S in HSB refers to saturation.
Hue, saturation and brightness explained
  • Hue refers to the perceived difference between one colour and another and accounts for colour names such as red, yellow, green or blue.
    • Hue can be measured as a location on a colour wheel and expressed in degrees between 00 and 2590.
  • Saturation refers to the perceived difference between one colour and another in terms of purity.
    • Saturation is measured between a fully saturated colour (100%) and an unsaturated colour (0%).
    • Saturation determines the vividness and richness of colours. Highly saturated colours appear vibrant, while desaturated colours appear muted or pastel-like.
    • A fully saturated colour is produced by a single wavelength or a narrow band of wavelengths of light.
    • On HSB colour wheels, saturation is usually shown to increase from the centre to the circumference.
  • Brightness (colour brightness) refers to the difference between a hue that appears bold and vivid at maximum brightness (100%) and then appears progressively darker in tone until it appears black at minimum brightness(0%).
  • Colour brightness is often apparent in the difference between the way a colour appears to an observer in well-lit conditions compared with its subdued appearance when in shadow or when poorly illuminated.

Saturation & colour

About saturation & wavelength
  • Saturation is one of the three primary properties of colour, alongside hue and brightness.
    • A colour looks saturated when made by a single or a small range of wavelengths.
    • A colour made by one wavelength of light is often referred to as a pure spectral colour.
    • Unsaturated colours appear faded due to a wider range of wavelengths.
    • Saturation is linked to the complexity of light.
Light complexity
  • Light complexity, linked to saturation, refers to the quantity and range of wavelengths of light used to create a colour.
    • Spectral colours are simple because they consist of just one wavelength of light.
    • Bands of colour are relatively simple because they are composed of a continuous range of wavelengths.
    • Non-spectral colours can be produced from a mix of many wavelengths from different parts of the spectrum, making them the most complex.
  • In reality, colours are often produced by complex combinations of wavelengths.
  • The greater the number and spread of wavelengths across the visible spectrum present in a colour, the lower the saturation.
  • The human eye can perceive millions of different colours due to the complex interactions of wavelengths and the eye’s colour receptors.

Saturation & colour models

About saturation and colour models