NR 422- Advanced GIS Cartography Jim Graham Spring 2009
GIS Professionals Produce GIS reports, articles, posters, and web sites that are: –Accurate & Precise –Astatically pleasing –Informative –Legal –Include the standard cartography elements: Spatial data, legends, scale bars, north arrows, regional maps, credits, author(s), and projection & datum Are recognized as authors!
What is a map?
Questions Purpose: –What is the map trying to communicate? Audience? What data is available? What is the schedule? Required accuracy? What resources are available? –Software –Computers –Existing photos, graphs, maps
Maps by type General reference maps –Show a variety of fixed features –Water bodies, coastlines, roads, etc. –Topographic maps Thematic or special purpose maps –Show one attribute or relationships between them Charts –Navigation by boat or plane
Maps by subject Cadastral: ownership Weather Research Recreational maps Planning Informational/Educational
Overall Style Antique Political Chart Academic Trail Maps Street Maps USGS Topographic Map Series
Levels of Quality Hand drawn MapQuest ArcMap PowerPoint Illustrator & Photoshop Quark Media: Electronic or paper
Types of content Contone –DEMS –Photos –Some statistical layers Spot color (drawings, vector) –Points –Polylines –polygons –Categorical rasters: Land cover GoogleMaps ESRI ArcMap Data Set
Map Production Computer Screens (CRTs, Monitor): –Emit light in a grid –About 100 dpi –Red, Green, Blue –Good for contone Printers: –Place ink on paper –Cyan, Yellow, Magenta, Black (CYMK) –300 to 2000 dpi –Good for spot color
Color Theory Light: AdditivePigment: Subtractive Computer Screens (CRT)Printers
Hue
CIE Color Diagram
Color Separation
Process Color
Color Printer Process Get the layout right Test the margins on a black and white printer Test the color print Adjust the colors until they look good Show it to others including target audience Cut off a white border if desired
Offset Press Professional grade Large numbers of copies –$500 for 500 copies –Cheaper for additional copies Each color on a separate “plate” Can mix special colors Almost all magazines and books are printed on offset press
Pre-Press Process 1.Talk to the printer! 2.Follow color printer process 3.Take the file and the color print to the process printer 4.Process printer creates “photo ready art” 5.May do a test run 6.Approve final output
Paper Paper is graded by “hardness” –Newspaper –Office paper –“Hard” paper (Hammermill) –Glossy paper Colored paper –Dark colors rarely work with computer printers –Use white paper and print the background solid
Using ArcMap with GA Applications Prepare your map elements File -> Export Select the appropriate file type Resolution as specified by the printer: –With spot color: 300 to 1000 dpi –Without spot color: 150 to 200 dpi –Files will be big! Import into the other application –Add backgrounds, callouts, redo the legend
Export File Formats Contone: –JPEG –TIFF with JPEG compression Spot Color, Line Drawings –GIF –PNG –TIFF with LZW or run-length compression Combined: –JPEG with high quality (low compression) –TIFF without compression
Using Color Pastels - calming Saturated colors – fun, exciting Young: –Red, blue, green, saturated Older: –Blue, green, red, unsaturated Color preference varies by culture! 10% of men and 0.5% of women are color-blind (poor color discrimination)
Background Color Sets the tone –Black – dramatic –White – technical –Green – comforting, natural –Red – exciting, danger –Beige – soothing –Orange, yellow – warm Should not be bright Should compliment the content
Borders Neat lines – contrast background: –Light background: black –Dark background: white or yellow Large regions – typically black Dashed for smaller subdivisons
Solid areas Oceans: light blue Regions: pastels Patterns: going out of style? –Patterns of sparse vegetation, rocks, etc. are ok. –Hashed areas only used for special purpose
Networks Standard symbols for highways, roads Blue with black outlines for rivers, black lines for streams GoogleMaps
Points, “Marks” or Symbols Standard when available Easy to identify and remember Size: big cities larger National Geographic
Standard Symbols from the USGS
Overlays Informational balloons Photos Call outs National Geographic
Labels Typically black or a dark color Drop shadow or “halo” to highlight on a dark background Size matches importance National Geographic
Label Placement Typically horizontal Large roads and steams the label should be above the feature and curve with it Labels in regoins can follow it’s shape Should always be right side up Should not overlap with other labels and symbols
Positioning Guidelines Entirely on land or entirely on water Match orientation of the map –Small scale: match parallels –Large scale: match bottom edge Not curve unless needed If out of orientation, should have a slight curve Avoid wide spaces unless needed Never upside down Elements of Cartography
Label Placement Place name 1 Place name 3 2 Place name 4 Place name Place name 5 Place name 6 Place name 7 Place name 8 Place name 9 Place name 10 Elements of Cartography
Visual Variables Primary: –Shape –Size –Orientation –Color Secondary (Pattern): –Arrangement –Texture –Orientation
Map Elements Title Spatial Data w/neat lines Regional maps Scale bars North arrows Text: Author, data, projection, datum, sources, descriptive Grid lines and margins Magnetic declination: navigation maps
Regional Maps Enough for the user to identify the area –US map does not need regional Some maps need multiple: –Global –Regional –Local
North Arrow Style should match overall map style North points to true north Must follow lines of longitude (meridians) at the location of the arrow (ESRI does not do this automatically!)
Scale Bars Who is the audience? What measures for distance do they use? Units: Degrees, metric, English? Always use metric (SI) or degrees for scientific maps Must be readable Which region does it match?
Techniques Classification Simplification Exaggeration Generalization
Classification Express the salient character of a distribution Similar attributes into categories Create “typical” attribute for an area Clustering –Combining features at small scale (large extent) –Combine related features that are close together
Simplification Must reduce the detail of the map while maintaining it’s informational content Small-scale maps: –Find points that represent clusters –Polygons can be become points –Multiple points can become one
Exaggeration Exaggerate a feature of interest –Elevation –City size –Feature size Buildings Bridges Monuments
Generalization Reduces the size of the data (in bytes) Reduces detail Reduces interest in the generalized item
Composition Spatial data should be the focus, set the stage, and take up the most area (typically) Legends, scale bars, credits and other items fill in the gaps This makes each map layout unique Try different arrangements until you find the one that “looks best” (show it to others)
Map Element Placement Title at the top –Sometimes vertically on the left –Rarely on across the bottom In or around the map? –Either way it must stand out! Title