Ethan Montag


This article may be accessed on the publisher's website (additional fees may apply) at: It may also be accessed on the author's website (additional fees may apply) at: The performance in judging values in a univariate map encoded using five different color scales was tested in eleven subjects. Digital elevation maps (DEMs) were encoded using: 1) an RGB gray scale (RGB), 2) a gray scale based on CIELAB L* (L*), 3) a L* scale with an added red hue component (Red L*), 4) an L* scale with continuous hue change (Spectral L*), and 5) a gray scale based on luminance (Luminance). Performance was tested using an Evaluation task and a Production task. For both tasks judgments were made both with and without legends for all five encoding schemes. The results show a significant effect of choice of encoding scheme, the presence or absence of a legend, and an interaction between these two factors. Performance with a legend was significantly better than without one. The Spectral L* scale led to the best performance while Luminance encoding was the worst. This experiment is a first step in using quantifiable psychophysical procedures to evaluate the effectiveness of different color encoding schemes on the interpretability of multidimensional graphical images.

Publication Date



Note: imported from RIT’s Digital Media Library running on DSpace to RIT Scholar Works in February 2014.

Document Type


Department, Program, or Center

Chester F. Carlson Center for Imaging Science (COS)


RIT – Main Campus