Lab 4 [GIS6005]: Color Concepts

Comparison of Color Ramps

The three sequential, single-hue color ramps shown above demonstrate different methods for making a good selection of six contrasting colors. 

In a linear progression (see A), the same interval within each of the RGB ranges is used for all steps. A disadvantage of this simple method is the contrast in the darker range is more difficult to discern. 

One possible correction to this is to create an adjusted progression color ramp (see B), where the interval varies within each of the RGB ranges so that larger steps occur near the darker range. 

Finally, use of the ColorBrewer tool (see C) is a faster alternative to creating a sequential, 6-color color ramp. In this case, the tool adjusts the steps within each RGB range to more optimally distinguish the colors at both the darker and lighter ends of the range.

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