School of GeographyFACULTY OF ENVIRONMENT

Introduction to Cartography

What is Cartography?

• Art/science/technology of making maps

• Beauty vs. usefulness

• Cartographic design is a complex task

• Unlimited options (16 million colours, many kinds of lines and symbols)

• A good map makes it easy for a reader to acquire your intended information by:

• Depicting data effectively

• Reflecting the relative importance of features

• Reducing distraction

Cartographic Objectives

• Map Objectives (Why?)

• Highlight spatial relationships

• Illustrate analysis results

• Convey information

• Easier comprehension of complex events

• Design Objectives (How?)

• Fulfill communication objectives

• Assign meaningful symbology

• Fulfill map objectives

• Ensure truthful depiction of reality

Issues of Detail + Symbology

• How much detail should I include?

• Depends on generalisation and scale

• E.g. Small scale – not interested in detail

• What symbols should I use?

• Qualitative: Can vary colour, shape, texture, pattern

• Patterns: repetitive type of symbol used for areas (e.g. swamps)

• Consider effects of reduction, e.g. paper + photocopier

• Quantitative

• Shading / intensity

• Size of symbols

Colours/Special Effects

• How many should I use?

• A maximum of 12 different colours

• A maximum of 7 to 8 shades

• Employ patterns/textures/text if you need more categories

• Consider how the map will be disseminated

• Colour on screen (16.7 million) different from printer (256 colours)

• Avoid special effects:

• squares of black and white/lines – 50% - vibration effect

• same shading on two different backgrounds

• use of lines (diagonal, vertical) as they imply directionality

Limitations of the Eye

Examples of Special Effects

• Avoid use of these in your maps:

Legibility of Symbols + Text

• Size of symbols?

• Have to know what your map is being used for

• At which distance will the map be viewed? E.g. a wall map? Reading distance? At a smaller distance, the symbols can be smaller

• Text issues?

• Text colour vs background colour (to get a good contrast)

• Uppercase vs lowercase (use a combination )

• No fancy fonts / avoid mixing font types

• Perfect vision?

• Not everyone has this – not too crowded, enough contrast between background and symbols, background + text

Cartographic Specifications

• Perception threshold = legibility of smallest detail

• Line thickness should not be less than .1 mm

• Points: 0.5 mm for points

• Separation threshold = distinction between adjacent features

• > 0.2mm e.g. road and rail road line

• Differentiation threshold = smallest difference between the nearest same size symbols, e.g. proportional symbols – can do this by artificially making symbols larger to increase the contrast

Visual Balance + Hierarchy

• Center of the map

• Visual weight

• Size, colour (value + intensity), how close things are to the edge (e.g. things on right have more visual weight)

• E.g. if put a large north arrow on the map, map is not good because the eye goes there first

• Gaps: should be avoided in the bottom but ok at the top (i.e. above the visual centre

• Do not want other elements to compete with the main map

• Make easy to use scale bars

Which is Most Balanced?

What About This One?

And One Final One….

Map Elements

• Title (avoid ‘Map of…’)

• Author and date of the data

• Map body

• Legend

• Scale bar / representative fraction

• Date of the map

• North arrow

• Projection

• Sources of the data, licensing

• Water Mark

Layout View in ArcMap

• Map content is contained in a data frame

• Layers, symbols and feature-based text (labels)

• Map elements

• Legends, scale bars, north arrows, graticules, et.

• Text, pictures, graphics added to the page

• ArcMap Data View vs Layout view

• Data view: used for exploring, displaying, querying and analysing spatial data

• Layout view: shows the virtual page upon which the map content and map elements are placed

Starting a Composition in Layout View

Page Layout Toolbar

• Draw layout items in Draft Mode

• Faster page navigation

• Can turn on all items or just an individual element

• Pause drawing button

• Use if you change feature symbols, label property, layer draw order, etc.

Refresh

Pause

Layout View

Data View

Active Data Frame

• Can only have one data frame active at once

• Active when bold in the table of contents + marquee around it in layout view

• To make a frame active: right-click Activate OR click + Alt key OR click on the window in Layout View

Layout View in Draft Mode

• Can move elements around without the map redrawing

Page Layout Aids

• Rulers, guides and grids

• Snap graphic elements to layout aids

• Settings layout aids

• Tools Options Layout view tab

Adding Map Elements

• Scale bar - adjust division values or adjust width

• Use Legend Wizard

• Graphics, Pictures: Use graphics toolbar

• Can convert any element to a graphic

• Grids and Graticules (reference systems)

• Use where north is not constant across the map or map is not to scale

• Graticule (geographic)

• Measured grid (projected)

• Reference grid (index grid)

• Are a property of your data frame – Grids tab

Adding a Water Mark

• Always add a water mark

• Needed for maps at a scale of 1:10,000 or greater but best practice is use all the time

• Load these into ArcMap

• 2X and 5X watermark files

• Use the Georeferencing toolbar: View Toolbars

• Put the watermark file into the drop down list

• Fit to display

• Ask your GIS team for more details

Map Templates

• Create maps from .mxt files

• Can use predefined ArcMap templates

• Create custom templates

• Use the LCC template

• Looking at this tomorrow!

Extent Rectangles

• Add an extent rectangle to an existing data frame

• Shows position of one data frame relative to another

• Extent rectangles are dynamic (will automatically update if changes if you zoom in on big map – extent rectangle changes)

• View Data Frame

Properties

Extent Rectangles tab

Mapping Resources

• Technology trends in GIS – Cartography

http://www.esri.com/technology_trends/cartography

• GIS for Map, Chart and Data Production

http://www.esri.com/industries/map-chart-dataproduction/

• ESRI Mapping Center

http://mappingcenter.esri.com/

Using Layout View in ArcMap

Hands-on Exercise #4