The title is usually the largest font size of all lettering on the layout, however, it should not dominate the map graphic itself.
The title may or may not be in a box and does not need to be at the top of the page though it often is. For published materials e. The reader must be able to determine the relationship between a unit of measure on the map and a unit of measure in the real world.
Commonly this is done by a north arrow or compass rose. Orientation may also be shown by graticule or grid marks e. By convention north is towards the top of the page thus some maps do not have north arrows , but the orientation must still be given for a 'proper' map. North does not have to be at the top of the page and a north arrow is essential in maps where it is not.
The border is often the thickest line on the map and should be close to the edges of the mapped area. The distance between the map and the border should be the same on all sides balanced. Features that have less contrast appear to belong together. Figure 2. Symbols A and text C that are too small are illegible. Appropriately sized symbols B and text D can be easily distinguished and read.
Using familiar geometric icons, such as an airplane for airports E , helps readers immediately understand the meaning of the symbol. More complex symbols, such as a mortarboard for universities F , need to be larger to be legible.
Legibility is the ability to be seen and understood. Many people strive to make their map contents and page elements easily seen, but it is also important that they can be understood. Legibility depends on good decision making when selecting symbols. Choosing symbols that are familiar and are appropriate sizes results in symbols that are effortlessly seen and easily understood Figure 2.
Geometric symbols are easier to read at smaller sizes. More complex symbols require more space to be legible. Visual contrast and legibility can also be used to promote the other design principles: figure-ground organization, hierarchical organization, and balance.
Figure 3. It is sometimes hard to tell what is the figure and what is the ground A and B. Simply adding detail to the map C can help map readers distinguish the figure from the ground. Using a whitewash D , feathering E , or a drop shadow F can also help. Figure-ground organization is the spontaneous separation of the figure in the foreground from an amorphous background. Cartographers use this design principle to help map readers focus on a specific area of the map.
There are many ways to promote figure-ground organization, such as adding detail to the map or using a whitewash, a drop shadow, or feathering.
Figure 4. When the symbols and labels are on the same visual plane A , it is difficult for the map reader to distinguish among them and determine which are more important. For a general reference map B , using different sizes for the text and symbols e. When mapping thematic data C , the base information e. As noted in Elements of Cartography , Sixth Edition, one of the major objectives in mapmaking is to "separate meaningful characteristics and to portray likenesses, differences, and interrelationships.
You can think of a hierarchy as the visual separation of your map into layers of information. Some types of features will be seen as more important than other kinds of features, and some features will seem more important than other features of the same type. You should not only choose the right projection but also make any necessary modifications to the projection to make it serve the purpose of the map. A good example is repositioning the central meridian the origin of the longitudinal x-coordinates of the map projection to the center of the mapped area.
A telltale sign that the mapmaker did not do this is that the map is tilted in the center so that north is not up Figure 1. Simply modifying the projection to position the central meridian at or near the center of the mapped area will take care of this problem. Figure 2: Curvilinear lines can help you determine if the data is too detailed for the map A or too general for the map D. Examples B and C are the better solutions. Another thing to check is the level of generalization of the data.
This relates to the map scale. Small-scale maps that cover a larger area look better when the data is more generalized. Large-scale maps that show a smaller area require more detailed data. Generalization also relates to the symbology you use. Thinner lines reveal more about the true geometry of the features. Thicker lines can mask jagged edges and areas where features don't line up exactly which is a trick cartographers use to fix some problems.
Two clues that will help you tell if your data is at the right level of generalization can be found when you examine a curvilinear line, like a river or a boundary that follows a natural feature e. Is it drawn with what will likely be the final symbology?
Does that line collapse in on itself, causing portions to appear as polygons instead of lines Figure 2A? This apparent increase in feature dimensionality from 2D lines to 3D polygons is a good indicator that the data is too detailed for the selected map scale and symbology. Conversely, map lines that have sharp angles where they should appear smooth Figure 2D incidates the data is too general.
Solutions for both problems include replacing the data with a more appropriate dataset, geoprocessing data to bring it more in line with the map requirements, and using some cartographic tricks to mask the problem like modifying symbology. Symbology is critical. If your map readers cannot tell what a symbol is or what it means, your map is potentially misleading or even useless. Three things will help make your symbology more easily understood by map readers: familiar symbols, intuitive symbols, or good explanations for symbols that are not familiar or intuitive.
From their previous map use experience, many map readers will already be familiar with some symbols, such as a blue line for a river or a green polygon for a patch of vegetation. When possible, use these familiar symbols.
For features that do not have a familiar representation, try picking a symbol that your readers will intuitively understand such as a picture of a person walking with a stick to symbolize a trail. For symbols that are not familiar or intuitive, provide a good explanation in a legend or through explanatory text.
Figure 3: Color hue and shape, and to a lesser extent orientation, naturally evoke qualitative differences among features. Image courtesy of Map Use , Sixth Edition. To also improve clarity, when you have a number of features that will overlap, try using a cased symbol one with an outline. This will let readers distinguish all the features, even when they overlap one another.
To choose the right symbol, first determine if the data is qualitative signifying difference in type or quantitative signifying a difference in magnitude. The visual variables i. For qualitative data, color hue e.
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