Good Map / Bad Map

Cartography can be a useful or damaging tool when trying to convey ideas or messages. It doesn’t matter if you are looking at a road map on the back of a napkin or a map published in the latest Ran McNally. Maps can either be helpful or hurtful. Whether making or looking at a map there are many important components that go into making a legible and easily understandable map. Color is the element that I will focus on in this entry.

Color can be used to not only enhance the visual attractiveness of the map but also the message or content of the map as well. There are many components within the subject matter of color usage. Hue is the difference between colors i.e. red, blue, or green. Value is the difference between lightness and darkness within a specific hue or color. Hue can be used to differentiate between different elements on a map such as a black road or a blue river. Value can be used to show population distribution from higher density populations shown as dark and lower density populations being shown by lighter colors. Contrast or figure ground is also another important tool used within the theme of color usage. Employing the use of figure ground you can create a pop out effect which draws the reader’s attention to a specific area of detail within your map.

When making use of any of these tools it is important to know that there are also limitations. Too many colors can make a map hard to read and too slight of change in shades of the same color can be hard to differentiate. In the map below the red makes nice usage of figure ground. It is easy to tell that the red roads are the major roads on this map or at least the one they want you to notice. However the yellow lines or roads on this map are hard to see against the dull greenish yellow backdrop. to me the biggest fault in this map is the use of the color blue. The blue is used to indicate rivers and river names but also (I think) city block names or areas of the town. It is also used to create a grid to section off the map. Using the same color for multiple tasks can be confusing to the reader and cause confusion among the map viewers. When using color it is good to know the preconceived notions of what your audience thinks certain things should be colored. For instance the blue in the U.S. is often used only to signify rivers or hydrologic features. In this map they do that but also use the same color for multiple features which should be avoided when possible.Color can be a useful tool when creating maps. However in the case of this map I think that it creates more confusion and makes the map hard to read.