VALUE VERSUS CHROMA IN COLOR SCHEMES ON QUANTITATIVE MAPS

Abstract

Graphic portrayal of the dimensions of value (lightness) and chroma (intensity or saturation) of colours permits greater understanding of how these dimensions affect map readers' reactions to colours on quantitative maps. Specifically, when changes in value and chroma on test maps of a choropleth type are correlated with reader's reactions to these test maps it is found that chroma is extremely potent as a variable in a map reader's perception of varying magnitudes, and if not carefully controlled can render a colour scheme quite ineffective.