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User:Shaund/West End

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Drawing a map with QGIS

Note - this description is based on my limited experience with QGIS. The version I used was 1.7.4 for Windows.

Set-up

  1. Download and install QGIS. Versions are available for Windows, Linux and Mac OSX.
  2. Download/enable three Python plug-ins -- SimpleSVG, Shaded Relief and GdalTools.

Obtain data

GIS software works by reading data encoded with geographic information (e.g, longitude, latitude, elevation) and renders it as a map. Common file types that QGIS can read are:

  • DEM (Digital Elevation Model) - contains geo-referenced elevation data
  • GeoTIFF - contains geo-referenced elevation data (note - not all TIF files are geo-referenced)
  • KML - a mark-up language kind of like XML that stores vectors, is commonly used by Google Earth
  • SHP (Shapefile) - stores geo-referenced vectors, can be a very powerful format as SHP files are linked to database files with additional information on each vector (shape)

1. Obtain Elevaton / Bathymetry data (if desired)

Elevation data is usually found in DEM format, although it can be as a GeoTIFF in some cases. Good sites for elevation and bathymetry data are:

  • ETOPO1 - Elevation and bathymetry data good for maps covering large areas. GeoTIFF format. The image is downloadable as one (very large) tile so it can be difficult to manipulate.
  • SRTM - Elevation info only that covers 50 deg S to 60 deg N. There are a number resolutions:
    • SRTM1 - the finest resolution, only available for the US
    • SRTM3 - data files are 1 deg latitude by 1 deg longitude and available for the entire world
    • SRTM30 - DEM files that cover large parts of the world. A good substitute if the ETOPO1 file is too big.
  • GeoBase
  • USGS

Import data

Add colour to elevations

Modify layers

Create shaded relief

Remove scale bar, north arrow and copyright

Export as SVG

Clean-up in Inkscape

Variants

Actions

Destination Docents

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