Rainbow

Sharp transitions between constant hues – perceived as jumps in the data

world map with geoid height color mapped with Rainbow has yellow create strong contrast even where the difference is small

Color schemes lie

If it gives the wrong impression to data we know – what does it do to data we don't?

Marie Curie's face, earth, and an apple mapped in Jet, greyscale and Batlow respectively highlights the visual distortion of Jet.

Color not alone

Use other indicators than color to convey meaning

form fields with thin colored borders (hardly) indicating error/success. Additional icons help.

Width matters

Colors are easier to discern in larger areas

form fields with wider colored borders are easier to read

Requirements

  1. Distinct for all people, including colour-blind readers
  2. Distinct from black and white
  3. Distinct on screen (and printed on paper, but less so)
  4. Matching well together

Datatype matters

Qualitative
Nominal or categorical data, where magnitude differences are not relevant.
Lines in plots and text in presentations.
Diverging
Ordered between two extremes where the midpoint is important.
Positive and negative deviations from zero or a mean.
Sequential
Ordered from low to high.

Qualitative – Muted

Where magnitude differences are not relevant.

the Muted color scheme magnetic field plot in Muted scheme
  1. rose
  2. indigo
  3. sand
  4. green
  5. cyan
  6. wine
  7. teal
  8. olive
  9. purple

Diverging – Sunset

Where the midpoint is important.

the Sunset color scheme world map with geoid height indicated by Sunset colors

Sequential – Iridescent

the Iridescent color scheme Iridescent example plot of electron density by altitude and longitude

Muted – Sunset – Iridescent

Muted color scheme Sunset color scheme Iridescent color scheme
geoid height plot using Rainbow geoid height plot using Sunset

lars-henrik.snow@irf.se

References