Lesson 5 Introduction and Action List

In this lesson, you will use an urban planning topic to learn more about feature symbolization and map composition. Understanding basic cartographic principles for organizing and displaying geographic data is fundamental to communicating the results of the GIS analysis process. You will add data from an online portal, customize the symbology for polygon and line features, manipulate feature labels, add map elements (title, legend, scale bar, etc.), and create map layouts.

At the successful completion of this lesson, students should be able to:

1. Apply a custom color scheme,
2. Symbolize polygon and line features,
3. Label features,
4. Add map elements to a layout, and
5. Create a custom layout.

Problem

The City of Kalispell, Montana is a thriving community located close to the popular attractions of Glacier National Park, Flathead Lake, Whitefish Mountain Ski Resort, several National and State forests and parks, and the Bob Marshall Wilderness area. Kalispell is the governmental, retail, professional, and medical center of the Flathead Valley, which serves approximately 140,000 people in northwest Montana. The most recent population estimate for Kalispell is 22,052. The City of Kalispell [1] is heavily invested in tourism, which remains a strong economic driver for the region.

The City of Kalispell is making a big push for new businesses to invest in the area, particularly in the area of adventure tourism. They need to create maps to send to commercial outfits that are evaluating where they will invest next. In this exercise, you prepare maps that show zoning, roads, proximity to tourist attractions, and future development areas that would be of interest to stakeholders.

At the conclusion of the exercises, you should be able to present a map that can be used to show which areas of the city are zoned appropriately and are open to development for a new adventure tourism business.

Important Keywords

Make sure you are familiar with these key terms that can be found throughout this lesson and course. Use the fun Quizlet activity below to help reinforce your learning of the terms.

• Cartography
• ColorBrewer
• Lookup table
• Map element
• Map layout
• Map template
• Reference Scale
• Visual Hierarchy

Action list

Lesson 5 Concept Gallery / Background Reading

Map Composition and Visual Hierarchy

Your job as a map designer is to organize the display so the viewers get “the greatest number of ideas in the shortest time” (Tufte 1983). Symbolizing attribute data as effectively as possible (by skillful use of the graphic and typographic variables) is one step toward that goal. Another step is map composition. Map symbolization is about representation; map composition is about organization. One objective of map composition is that the most important feature classes on the map should appear to be most prominent, while less important feature classes should recede into the background. A second objective is to assemble all the graphic and typographic components that make up a map display (title, legend, scale bar, north arrow, documentation and credits, as well as the map itself) into a balanced spatial arrangement. Map composition therefore involves both hierarchical organization and planar organization (Dent 1998).

The best maps are those in which graphic and typographic features appear to inhabit separate layers, whose order is determined by their relative importance. For example, thematic symbols normally should appear to be most prominent, followed by the map title and legend. The land and water of the base map usually appear to reside in the background. Reference elements such as the scale bar, north arrow, graticule, and credits are less prominent still. The effect of graphic elements organized into levels of prominence is called visual hierarchy.

A visual hierarchy can be achieved only if you, as the map designer, first develop a conceptual hierarchy of graphic and typographic features. This requires a clear understanding of the intended audience and purpose of your map. After the hierarchy is conceptualized, it can be implemented by manipulating the graphic and typographic variables. For instance, it is well known that when swatches of red and blue are viewed side by side at the same viewing distance, the red swatch appears to advance while the blue swatch tends to retreat. More subtly, darker, more saturated colors tend to appear above lighter, less saturated colors. Black type appears above gray type. Large symbols and type are more prominent than smaller symbols and type. Objects with strong edges (e.g., bounded with thin black lines) tend to advance over objects with soft edges (e.g., no boundary line, or a boundary line colored the same as an area fill). An object that overlaps another object appears to have risen above it.

Finally, the horizontal position of an object in the display space also affects prominence. Because western viewers’ eye movements tend to begin in the upper left corner of the display, and then wander toward the center, objects located in those positions tend to appear more prominent than objects located elsewhere. Horizontal positioning is called “planar organization.”

This lesson surveys the principles of map symbolization and map composition. Effective symbolization is achieved by matching qualitative and quantitative attribute data with the graphic and typographic variables that represent them best. In general, symbol size and color lightness are effective graphic and typographic variables for representing ordinal-level quantitative data. Color hue, symbol shape, and pattern are appropriate for qualitative attribute data. The position of graphic features on maps is normally not variable, but positioning typographic labels is a crucial and demanding task. Graphic and typographic variables can be used to organize feature classes into visual hierarchies that express the relative importance of the contents of the map, and to help viewers to make sense of complex images. Skillful layout of map components ensures that viewers will not be distracted by an awkward arrangement. The objective of map design is to foster insightful map analysis.

Hue as a Variable of Color

The interpretation and connotation of a set of hues may be ambiguous. Say, for example, you have two symbols that are alike in every way, except that one is blue and the other is green. Hue often does not adequately denote a difference in quantitative distinction between features. If you were to interview one hundred passers by, and ask each one to point to the symbol that represents “more” of something, chances are you’d get about fifty guesses for each color. In general, setting aside intrinsic differences in lightness, hues are more effective in representing qualitative attributes than quantitative attributes. Often differences in land use are set apart by different hues. Convention dictates the selection of these representative colors, as seen in Figure cg 5.1 below.

Color blindness is another factor that can make map color selection and interpretation confusing. About eight percent of men and less than one-half percent of women have trouble telling reds and greens apart, and certain other pairs of hues with similar lightness. To make sure everyone in your audience can differentiate all the colors on your maps, choose a palette of hues that vary noticeably in lightness. In particular, if you wish to use a spectral color scheme that accommodates most color deficient viewers, use purple, blue, blue-green (instead of greenish-yellow), yellow, orange, and red (Brewer 1999).

Color Specification

GIS software packages provide a limited palette of standard colors that you can use to symbolize spatial features. In addition, they provide color specification tools for defining custom colors. Quite a few different color specification systems exist. Among the ones commonly offered in GIS packages are RGB and HSV. Other color specification systems used widely in the publishing industry include CMYK and the Pantone Matching System (PMS). All involve creating colors by mixing proportions of three or more primary colors.

The illustrations above show ArcGIS Pro’s standard color palette and color specification interface utilized in the Legend Editor. As seen in Figure cg 5.2, the standard fill colors allow the user to choose from an existing array of colors, while the color selector, seen in Figure cg 5.3, allows the creation of alternative colors. In the color selector, the user can adjust color variables in the RGB specification systems. A color can be manipulated by entering values between 0 and 255 in the boxes at the right or by dragging the sliders on the horizontal bars at the left. The two sets of controls are linked so that changing one changes the other automatically.

Color perception relies in part on photoreceptors called “cones” in the retina of the eye. Although the spectral sensitivity of cones extends across the entire visible spectrum, sensitivity peaks at wavelengths that correspond to the colors red, blue, and green. The peaks allow engineers who design color televisions and computer monitors to produce the sensation of “full” color by mixing only three colored lights: red, green and blue.

Color specification tools in GIS software packages like ArcGIS Desktop enable users to create custom colors by varying the intensities of red, green, and blue lights emitted by the phosphors that coat the inside of your computer screen. Intensities range from 0-255 because each red, green, and blue specification is stored in memory as an 8-bit binary integer, which yields 256 (2⁸) possible unique values. The complete gamut of possible colors thus numbers 256³, or approximately 16 million colors.

Mixing red, green, and blue light is not a very intuitive way to create custom colors. An alternative is to use a specification system based upon the perceptual dimensions of color. Numerous perceptually structured color models have been developed. Some are more rigorous than others. Unfortunately, the most rigorous, such as the Munsell system, tend also to be the hardest to implement, and so are seldom included in GIS software packages. Standard color specification tools, therefore, commonly employ a quasi-perceptually structured color model called Hue, Saturation, and Value (HSV).

Pattern as an Element of Map Composition

Line and area features can be symbolized with patterns. Patterns are useful for differentiating categories of line features, such as county, state, and national boundaries. Patterns are also useful when two area features need to be superimposed without obscuring one another. For example, a floodplain may be superimposed over a zoning map by symbolizing the floodplain with a cross-hatch pattern that overlaps the colors used to represent the zoning districts.

The illustrations above and below show the symbology pane, which is used to specify patterns for line features (above) and area features (below) in ArcGIS Pro. Line features may be symbolized with single line, double lines, or patterned lines. In this context, patterns consist of repeated sequences of point symbols aligned with the line feature.

Area features can be symbolized with either a single foreground color, a patterned foreground and a transparent background, or a patterned foreground with a background of a different color.

Basic Labeling Concepts and Conventions

The most important way typography adds value to maps is by helping map readers to identify spatial features. One of your most important tasks as a cartographer is to position labels on the map so that their associations with features are unambiguous. Attempts to automate label placement have been promising, but so far have not eliminated the need for manual editing. Indeed, label placement can be one of the most demanding and time-consuming components of the map production process.

In ArcMap, there is more than one way to add type to a map. They refer to a user-specified “label field” in the layer’s attribute table, but involve different degrees of interaction. The Label Features command affixes text to features automatically according to a user specified set of parameters to control label placement, scale and position.

A second labeling method, accessible as a pull-down under the Add Text tool on the Draw toolbar, is the Label Tool and provides for the individual placement of each label. This method works just like the Label Features command, except that instead of labeling an entire layer all at once, you label only selected features, one by one. The specification of labeling characteristics is still possible.

Labels are not selectable and the display properties of individual labels cannot be edited. If you want this kind of control over the text, then the labels can be converted into annotation. Annotation is stored information which includes a text string, a position at which it can be displayed, and display characteristics.

If you want to see outstanding examples of type positioning, take a close look at the National Geographic Atlas of the World, or any of the map inserts included with National Geographic magazine. Notice that National Geographic cartographers rarely use arrows or pointers to name features. Instead, they skillfully, even artfully, position place names so that names are unambiguously associated with places.

The distinguished Swiss cartographer Eduard Imhof published rules for type placement (for example, Imhof 1975), which have been expanded by subsequent authors. In general, labels must not overlap each other, and should not overlap other features, though the latter often cannot be avoided. Line feature labels should be positioned above the feature, as close to the middle of the feature’s extent as possible, and along a stretch that is as straight and as close to horizontal as possible. Place the label just far enough above the feature so that the descenders of characters g, j, p, q, and y do not overlap the line feature. Line feature labels should be rotated so that they run parallel to the feature. Labels should never be rotated more than 90 degrees, however. If the line feature is vertical, run the name on the left side reading upward if the feature is on the left side of the map, or on the right side of the feature reading downward if the feature is on the right hand side of the map. Letter spacing should be constant and reasonably tight. Space between letters reduces legibility, especially for words that consist of lower case letters. Labels should be repeated for very long features.

Type Size, Weight, and Font as Labeling Variables

As in most word processing and desktop publishing software, font size is specified in “points” in ArcGIS Desktop and other GIS packages. One point equals approximately 1/72″. The size of the tallest letter of a 12-point font is therefore a little less than 12/72″ tall. Originally, point sizes referred to the height of the metal block upon which letterforms were cast, and the block was necessarily a little larger than the tallest letter. This slight discrepancy persists even into the current era of digital typefaces. Also, you may notice that not all fonts are the same height at the same size.

Type legibility depends primarily on type size. Obviously, labels on maps usually need to be as small as possible. Minimum legible type sizes vary with viewing distance. Six point type is a safe minimum size for printed maps viewed from 18 inches under normal lighting conditions when the contrast between the type and the background is high. Eighteen points is a safe minimum for maps viewed from the back of a room in a public presentation, whether printed on paper or projected on a screen.

Type size is also a useful typographic variable for expressing ordinal relationships among map features. For example, four classes of cities, categorized by population size, are effectively represented with four different sizes of place names. “Weight” is another text variable that can be manipulated to establish a hierarchy of features. Weight refers to the thickness of the strokes that make up the letterforms. Some fonts are available in a range of weights, from light to semi-bold to bold to extra bold. These can be used to create categories of emphasis. These effect can be particularly useful when maps are crowded with labels whose size cannot be varied much.

Font is another typographic variable that can be utilized to differentiate feature labels. Thousands of unique typefaces have been developed over the centuries since visible languages were invented. Fonts designed for use in books, newspapers, and magazines vary subtly from generic letterforms. Decorative fonts designed to attract attention and impart style in advertisements and logos vary dramatically, sometimes so much so that the letterforms are barely recognizable. In general, text fonts rather than decorative fonts should be used for maps, since legibility at small sizes is crucial.

A typeface is a set of characters, numerals, and punctuation marks that share common characteristics, including stroke width, the presence or absence of serifs, and x-height. For example, Arial is a typeface characterized by wide, almost uniform stroke widths, no serifs, and a tall x-height. Typefaces consist of several fonts (e.g., Arial, Arial Bold, Arial Bold Italic, Arial Italic). Fonts are stylistic variations on typefaces. Stylistic variations that distinguish the fonts within a typeface include weight and posture (slant versus upright).

According to Brian Allen, a past student and a professional typographer, “Serifs are short cross strokes that originally acted as a lead-in to, or exit from, the main horizontal and vertical elements of a letter. They were first seen in ancient Greek and Roman stone inscriptions, and then in calligraphy written with a flat brush or broad edged pen (made from the reed plant, a goose quill, or metal).

Early printers in 15th century Europe made type that mimicked the letterform styles of the hand written manuscripts of the time, so calligraphic serifs came into use in the metal type. Over the centuries the styles of serifs became increasingly varied, from delicately fluted to thin straight lines to thick and blocky slabs.

The urgency of mid 19th century commerce helped the emergence of type without serifs, called sans (French for: without). Advertising handbills and broadsides frequently used tightly spaced, large and very bold sans serif letterforms in wood and metal type. By the late 19th century, text size sans serif typefaces were appearing. Their variety and use has increased dramatically over the past century, through several generations of typesetting and printing technologies, largely to signify a modernist sensibility, and most recently, a postmodern one.”

Besides serifs, another key difference between older and newer typefaces is the height of lower case letters relative to the upper case letters. Fonts whose lower case letters are relatively tall are said to have large “x-heights.” Large x-height, which is characteristic of many sans serif fonts, is a desirable characteristic for map lettering, since it leads to relatively increased legibility at small sizes.

Most text fonts have an italic version. Italic fonts were originally developed to simulate handwriting. One characteristic of italic fonts is that the letters are slanted forward.

Differences among fonts are akin to shape differences in point symbols. Both tend to connote qualitative rather than quantitative relationships among map features. For example, italic fonts are conventionally used to represent water features, perhaps because the slanted posture of italic type suggests a flowing stream. To ensure the visual coherence of a map presentation, font variations should be used sparingly. In general, use one or at most two different typefaces in a map or map series. Several fonts within the same one or two typefaces may be used together, however. If two typefaces are used on a map, one should be serif, the other sans serif.

Layout Organization

Planar organization is a fancy name for “layout.” The goal of this aspect of map composition is to arrange all the components that make up a map presentation: title, legend, scale bar, north arrow, documentation and credits, as well as the map itself so that the entire display forms a coherent whole. Like many other aspects of cartographic design, good layout is something few people will notice, but a bad layout attracts all kinds of unwanted attention.

Good layout is characterized by a sense of visual equilibrium. One way to achieve this is to balance the various components relative to the optical center of the display, which is located about 5 or 10 percent above the geometric center. Each component carries a visual weight determined by its location, size, shape, and other factors. In particular, according to Dent (1999):

• A component located above the optical center of the display appears heavier than if it were located below the optical center
• A component located in the right hand side of the display appears heavier than if it were located in the left hand side
• The further a component is located from the optical center, the heavier it appears
• Large components appear heavier than small components
• Compact, regularly shaped components appear heavier than irregularly shaped ones
• Isolated components appear heavier than those surrounded by other elements

That last factor brings up another important point about layout: your goal should not be to fill up every empty space! Experienced designers preserve a little white space here and there to keep the display from appearing overly cluttered. Furthermore, don’t be afraid to overlap components; its a useful trick for creating a sense of depth that most viewers enjoy.

In practice, map layout is a matter of dividing the available space into compartments for each component of the display. As you have just seen in ArcGIS, GIS packages typically provide specialized tools for map layout.

Additional Map Elements

In addition to the graphic variables, north arrows and scale bars frequently appear on maps. Because most of the maps seen by residents of the northern hemisphere are oriented “north up,” it may seem superfluous to indicate direction with an arrow. Even so, map makers have long been instructed that “all serious maps should supply the user with adequate direction-aids” (Greenhood 64).

An indication of a map’s scale should also be included in any reputable map composition. The advantage of a bar scale over a representative fraction is that the bar scale holds true even if a map is photographically or xerographically reduced in size. This quality only holds true if the bar scale is correct in the first place.

The preferred appearance of north arrows and scale bars is determined mainly by house style or personal taste. In general, however, it is advisable to keep these elements relatively small, simple, and unobtrusive. In no way should they compete for the viewer’s attention with the primary content of the map.

Map Presentation Media and Methods

GIS specialists tend to be minorities in the groups that use geographic information to make decisions. The majority is made up of groups such as design review boards, planning commissions, and the general public, who are not necessarily familiar with the process and output of GIS analysis. As a result, GIS specialists who produce geographic information need to communicate it effectively to non-specialists. The presentation of geographic information is therefore a crucial stage in the process of transforming data into information. Poor execution at this stage can undermine the impact of an entire GIS project.

Obviously, maps can be an effective way to present geographic information. Experienced cartographers start design projects by learning as much as they can about their audience, about the objectives of the presentation, and about the setting or settings in which the presentation will occur. Next, they adopt the presentation medium best suited to the expected conditions of use. Each presentation medium poses opportunities and constraints that shape subsequent map design decisions. If the characteristics of presentation media are not taken into account, unpleasant surprises are more likely to occur when a map is presented or published.

Hard Copy Media

The term,”hard copy output” refers to the production of black and white or color pages, posters, and transparencies printed on paper or plastic. As you know, various printing technologies are available, including laser and color laser printers, thermal wax transfer printers, ink jet printers and plotters, and electrostatic plotters. They vary in format from 8.5 by 11-inch letters to posters 54 inches by 150 feet or more. Some print on paper; some require special media. Printers vary also in the page description languages they understand. Some understand PostScript, and some understand the Printer Control Language (PCL), and so on. As a result of these and other variables, every kind of printing device produces a slightly different result. And, as you know, all printed pages look different from the same image displayed on your computer screen.

What you see is light wavelengths of electromagnetic radiation within the narrow visible band of the spectrum. Most of the light we see is reflected radiation, such as light reflected from a printed page. The light emitted by a computer screen is transmitted directly to the eye (or it may be bounced off of a projection screen). Reflective (hard copy) presentation media pose different opportunities and constraints than do transmissive (soft copy) media.

Understanding why what you see on the screen is not what you get on your print is important to ensure the best result. Further, it is important to understand how humans perceive color and how you can use a tool called a “design guide” to select map colors and symbols to produce a predictable final product.

Color Perception and Specification

Our visual perceptual system interprets different wavelengths of light as different colors. The entire spectrum of colors can be recreated from a few primary colors. The primaries are different for reflective and transmissive media, however. Reflective media create colors by mixing four inks: cyan, magenta, yellow, and black. Cyan, magenta, and yellow are called “subtractive primaries” because perceived colors are created when wavelengths are absorbed (subtracted from) the light reflected from the printed page. For instance, as illustrated below, a mixture of cyan and yellow inks produces the color green by absorbing (subtracting) the red and blue wavelengths.

This exercise guides you through Part I of this week’s exercise.

1. Post comments and requests for help in the Lesson 5 discussion space. Please include illustrative screen captures with requests for help.
2. Some concepts and procedures introduced in this exercise will appear in the quiz in Lesson 6.

This exercise guides you through Part II of this week’s exercise.

1. Post comments and requests for help in the Lesson 5 discussion space. Please include illustrative screen captures with requests for help.
2. Some concepts and procedures introduced in this exercise will appear in the quiz in Lesson 6.

This exercise guides you through Part III of this week’s exercise.

1. Post comments and requests for help in the Lesson 5 discussion space. Please include illustrative screen captures with requests for help.
2. Some concepts and procedures introduced in this exercise will appear in the quiz in Lesson 6.

This exercise guides you through Part IV of this week’s exercise.

1. Post comments and requests for help in the Lesson 5 discussion space. Please include illustrative screen captures with requests for help.
2. Some concepts and procedures introduced in this exercise will appear in the quiz in Lesson 6.

In this part of the Lesson 5 Activity, we will create a two presentation quality maps. Until now, we have been working in the map display of ArcGIS Pro. We will now start working with layouts. In other exercises, student deliverables are very similar. In this lesson you can and should customize your map. There will be less instruction on exactly what to do and more suggestions on what you could do.

We will expect you to make presentation quality maps in this lesson. That means that you should make good choices about title, symbology, layer hierarchy, extra map elements, etc. Have you watched the videos from the Lesson 5 Concept gallery yet? When grading, we will expect that you have watched these videos and that you have tried to incorporate some of the information about map layouts. The Make a Layout in ArcGIS Pro video is only three minutes long. The whole Mapping: ArcGIS Pro: Mapping and Visualization video is informative, but if you want to skip around to get to the parts that pertain to this lesson – symbology, labeling, and layouts –that is fine.

If you haven’t been thinking much about what your maps convey to your audience in previous lessons, now is the time to do that. Be aware of the purpose of your maps. We do not expect to make you into instant cartographers with the concepts covered in this lesson, but we do want you to care about the quality of the maps you produce. Do you have an appropriate title? Are your symbols and labels legible? Does your legend help your audience understand everything that is displayed on your map? You should explain the choices you make in the project write-up. You will be producing two map layouts in this lesson. They should be different. Take the time to add different elements and make them each stand out in their own way. Map 1 will be a zoning map and Map 2 will show the areas that can be used for commercial growth and include an overview map that shows where Kalispell falls within the county.

Please refer to the course Calendar for the due date.

Creating Your Lesson Report

• You may prepare your report in any one of several formats: Microsoft Word (.rtf or .doc) or Adobe Acrobat (.pdf).
• Lesson reports should be formatted so that images are legible. Instructors can’t evaluate reports that contain blurry, shrunken images. If necessary, change your page orientation or size in page setup to make room for full-sized, legible images.
• Please use the following naming convention in your report file name: “LASTname_FIRSTinitial_Lesson5”. My name is Jane Doe, so my file would look something like: Doe_J_Lesson5.doc.
• Please remember to include the following information in your report: your name, lesson number, lesson criteria and a summary of project objectives (please do not copy text from the lesson), and captions for all images.
• Your deliverable should be a report that summarizes the project background/objective, your work, and conclusions drawn from the analysis.

1. Create your lesson report. We expect descriptions to be written in your own words. Your lesson report submission should include the following items:
   • Discussion of what you discovered in this lesson. Talk about the choices you made for your maps. For example: What is the purpose of your maps? Who is your audience, and how did you tailor your maps to your audience? Were there any trade-offs?
   • Screen capture or exported map of the final customized layout. Please include your name as part of the customized layout.
   • Include the results of the Try This! section in your report. This should be a *separate customized layout that is distinct from the lesson customized layout*. Please include your name as part of the customized Try This! layout.
2. Upload your lesson report.

Project Evaluation criteria include:

• Quality and Completeness: 85%
  All required elements should be present in your report.
• Timeliness: 5%
  Lesson reports must be submitted to the Lesson Assignment by the assigned due date. Most lesson deliverables are due on Wednesdays, one week from the start of the assignment (refer to the course Calendar for the exact schedule). Please make every effort to submit your deliverables on time.
• Creativity: 10%
  Adequate fulfillment of all the requirements for an assignment merits a score of 90 out of 100 percent. Ten percent (or a fraction thereof) has been reserved and will be awarded for lessons with content that exceeds that which is outlined in these instructions. Examples of such work include, but are not limited to: providing particularly good, lengthy descriptions and explanations in the maps’ captions; posing a few good questions concerning lesson content or experimenting with the software and demonstrating new skills or operations. This criterion is particularly important in this course as it differentiates lesson reports that are otherwise very similar.