Colour Discrimination and Identification

Question 1

Distinguish small color differences

Answer 1

• Small colour differences can be distinguished when the
  areas to be discriminated are:
  – large,
  – immediately adjacent to each other (share an edge near the
  viewed point)
  – displayed at the same time.

Colour discrimination is best when a sharp edge
separates the colours to be discriminated.
* When a smooth gradient separates two colours, the
difference of colour appearance is reduced.

Question 2

Guidelines for color discrimination and identification

Answer 2

Use no more than six colours to label
graphic elements
Use colours in conformity with cultural conventions
Use colour coding consistently across displays and
pages
Use colour coding redundantly with other
graphic dimensions
Don’t use colour coding on small graphic
elements
Use neutral grey surrounds where colour
judgments are critical
Avoid saturated colours
Colour blindness affects a significant fraction of
human beings.