1. Given current computer technology, color is seldom NOT an option
Color is fundamentally important to cartography and fundamentally confusing
In the past: traditional printed maps: expensive and difficult to use color
Given current computer technology, color is seldom NOT an option
color is often misused with new technologies
Exciting and Dangerous
Allows greater design options
color is confusing and there are no specific standards
Color is seen differently by different people
Viewing conditions
Emotional reaction
Additive and Subtractive
Color Models and Specifications
many different ways to specify colors

2. Electromagnetic Spectrum
Figure 14.1
Electromagnetic Spectrum

3. But much more sensitive
Color Perception
Retina
Rod Cells
No color detection
But much more sensitive
Cone Cells
Sensitive to
Blue, Green and Red

4. Figure 14.3

5. Applies to maps on computers
Figure 14.4
Color Theories
Additive
Applies to maps on computers
Subtractive
Applies to printed maps
Since almost all maps are made
on computers now…

6. Table 14.1

7. Components of Color Hue (color) Saturation (sometimes chroma)
Figure 14.5
Components of Color
Hue
(color)
Saturation
(sometimes chroma)
Intensity or purity
Value
Lightness or darkness

8. Figure 14.6

9. Figure 14.7
Color Models
HSV

10. Figure 14.8
Additive (RGB)

11. Figure 14.8
Subtractive CMY(K)

12. Lesser used color models
HSB/HSL
Basically the same as HSV
CIE

13. Device Limitations Gamut Web Safe Colors
Dynamic range of possible colors
Web Safe Colors
0,51,102,153,204, 255
20 % increments
Supposedly displayed exactly the same on almost all machines.
Makes a total of 216 different colors
Color Matching Systems
Pantone
Like picking out a paint color at Lowes.

14. Figure 14.9
Color interaction

15. Simultaneous Contrast

16. Successive Contrast

17. Visual Acuity

18. Advance and Retreat

19. Hysometric effect

20. Colors in Combination
Best combinations result from differences in lightness
Good background should be light or dark
Consistently pleasing objet colors – blue to green, others containing little grey
Unpleasent – yellow or yellowish – those containing large amount of grey
Must stand out and be vivid (string combined with grey ok)

21. Table 14.3

22. Table 14.4

23. Table 14.5

24. Color Conventions Blue for Water Red to Blue – Warm to Cool scale
Green to Yellow to Tan or Brown – Vegetation to bare areas
Different categories should be different hues

25. Table 14.6

26. General Harmony Rules Most people like pure hues and shades
Red better than purple
Black better than gray
Colors on opposite or next to each other on the color wheel harmonize best.

27. Color advise for maps:
Color Hue and Color Value and Choropleth Maps

28. One Variable Color Schemes
Qualitative Schemes
Binary Schemes

29. One Variable Color Schemes
Sequential Schemes

30. One Variable Color Schemes
Diverging Schemes

31. Two and Three Variable Color Schemes

32. Two and Three Variable Color Schemes