Tips for conversion Qualitative Schemes do poorly Inevitable light-to-dark ordering suggests a hierarchy Unrelated classes end up with similar grays
Tips for conversion Design for medium: will your map be printed/reproduced? Lightness variation is the key to a good grayscale color scheme Limit the number of classes for copiers (4 or 5 at most Ideally, your colors will perform in both color and gray
The end of color 1.Describe the hue, lightness, and saturation of colors 2.Plan and produce a color scheme with hue, lightness, and saturation suited to mapped data characteristics 3.Categorize color schemes as sequential, diverging, or qualitative 4.Adjust map colors for colorblind readers
The end of color 5.Adjust map colors for black and white reproduction 6.Adjust map colors to avoid misinterpretation caused by simultaneous contrast 7.Specify colors in CMYK 8. Specify colors in RGB
General-reference maps usually represent things we can see and touch Gen-ref maps are offer congruent representations of geographic space
The thematic map Also called the “statistical map,” “single- topic map,” or the “special-purpose” map Less literal than a general-reference map Two groups of thematic maps: qualitative and quantitative
The 2 kinds of thematic maps Quantitative thematic maps –Spatial aspects of numerical data Corn yield Per Capita Income Number of Tornadoes Population Density –These maps are concerned with amounts, or quantities –Can you tell the difference? –Is the attribute a quantity or a quality?
This here is a Thematic map: Lung cancer in white males, by Brewer Qualitative or Quantitative?
What’s the point of Map Design? The point of map design is to facilitate the communication of geographic information Good map design is like good writing –Eloquent –Efficient –Informative –Pleasing –Well-structured
Brewer’s 5 Questions 1.What information is being mapped? 2.Who will be reading the map? 3.Is the map content coordinated with written content or other graphics? 4.What size and medium will be used to display the map? 5.What are the time & budget and constraints on map production?
Who will be reading the map? AUDIENCE!! –If you were to write a book how would audience influence your writing? –Know your audience Are they novices? Are they experts? Maps to see (simpler) Maps to read (complex)
Map for experts –More symbols –Hydrants, meters, fittings, valves, laterals, road centerlines and edges, and sewage mains –A map to “Read” Map for novices or busy folks –Reduced info content –Simplified, shows only hydrants and water mains –A map to “See” Examples from Brewer
Perceptual Salience In a map context, perceptual salience refers to graphic prominence or obviousness What sticks out to a map-reader The most prominent features on the map are said to be “salient”
Perceptual Salience and Novices Recent studies (Lowe, 1999) prove that novice map-readers extract information based on graphic prominence as opposed to relevance Perceptual Salience and Thematic Relevance –Good map design pairs thematically relevant features with graphically prominent symbols –Bad map design often emphasizes irrelevant features, or fails to emphasize relevant features
Salience and Relevance: please consider your purpose and your audience
What size and medium will be used to display the map? How will you present your map? Some examples of map media: Computer screen, projected display for hundreds of viewers, color laser prints for a small group, b&w print for a town meeting, large plot for a wall, glossy magazine, backdrop for a tradeshow, television news map, 2-inch PDA screen, etc.
Resolution defined Resolution measures the smallest marks we are able to create within a display. It varies significantly across media Commonly expressed as dpi (dots per inch)
Match these media with their resolutions: Computer screen 27-inch color tv Laser printer Litho plate on an offset printer 12000 dpi 72 dpi 600 dpi 26 dpi
Viewing Distance Common sense: Features need to be enlarged to be legible from a distance Imagine these map-viewing scenarios & their viewing distances –Poster maps –Projected displays –In-car-navigation systems –8.5 by 11 inch printed map Consider viewing distance in the design phase
Which map for which distance? What’s different?
Layout and Hierarchy The foundations of smart, clean maps
Map Layout The organization of your total map presentation Important objects should be more prominently displayed Layout the arrangement of “map elements”