This is a difficult question because the best choice depends on the viewer’s task, on whether another visualization technique such as a height field is used in conjunction with color, and on the frequency content and noise within the data displayed.
Although the rainbow color map is universally inferior to other color maps, there is no color map that is better than all other maps in all circumstances.
The purpose of visualization is to effectively convey information to human viewers.
The selection of the best color map depends so critically on the data set and addressed questions that there is not a single best choice, but rather a collection of sets with different characteristics. The best solution would present the user with a choice whenever a color map is created, listing best types for each circumstance.
viewers can see details more readily when luminance contrast is present than when it is not.
Luminance is based on inputs from only the red and green channels—making it impossible to generate a uniform-luminance rainbow scale including deep blue.
The most obvious perceptually ordered color map with luminance contrast is the gray-scale color map.
Unfortunately, the early visual system converts from absolute brightness to brightness relative to surround, which distorts readings enough to produce errors of up to 20 percent of the entire scale