Colour constancy

Colour constancy is the ability to perceive colours as relatively constant, even under changing lighting conditions.

  • Colour constancy refers to the perceptual ability to compensate when changes in illumination would otherwise cause things to appear to change colour.
  • Colour constancy is an extreme case of chromatic adaptation that associates a particular colour with an object regardless of changes in lighting.
  • Colour vision relies on colour constancy as it allows us to perceive the colour of an object as stable, even when the intensity or spectral distribution of the illumination changes.
  • Colour constancy contributes to our ability to ignore shifts in an object’s colour when the source or type of light changes, such as when it moves from sunlight to artificial light.
  • While our visual system is usually successful at maintaining colour constancy, it’s not always perfect, and optical illusions can highlight these imperfections.
About chromatic adaption
  • Chromatic adaptation refers to the ability of our visual system to adjust to changes in lighting conditions, helping to keep the perceived colour of objects relatively stable.
  • Chromatic adaptation helps us perceive the colours of familiar objects as constant, even under widely varying lighting conditions.
  • Chromatic adaption means an observed colour stimulus such as a white surface is judged to remain white even as other projected or reflected colours fall upon it.
  • Chromatic adaption often becomes noticeable when comparing photographs of the same subject in changing lighting conditions.
  • Cameras try to mimic chromatic adaption through white balance adjustments, but differences in lighting conditions can still result in two photos of the same subject appearing different in colour.
Related diagrams

Each diagram below can be viewed on its own page with a full explanation.

References

https://en.wikipedia.org/wiki/Color_constancy