DIGITAL CARTOGRAPHY

Data Acquision Primary Secondary Field Surveys (Total Station and GPS Survey) Raw data collection Secondary Digitizing Scanning Importing from other GIS Sources Purchasing from CAD vendors Exchange with other agencies

Total Station Survey Coordinate data that is used to plot features on the earths surface are obtained Some total stations are also able to capture photo images

GPS Survey This can be RTK GPS or handheld GPS GPS techniques provide a low cost but fast and reliable data acquisition method

Digitizing Digitizing tablets Comprise of capturing device to capture points on map into work station AO tablets cost an average of USD 2000

Scanning Scanners employ sensors to read the data on paper maps, film or other analogue material into digital format. It is most useful for images and maps with dense line work

Satellite Imagery

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Aerial Photography

Data Storage There is a variety of storage media for Digital cartography DVD Rom CD Rom PC (Hard Disk) External hard disk Memory Stick etc

Data Output

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Data Output Plotters Printers VDUs

Plotters

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Visual Display Units

Tablet PC

Printers

Discussion Questions Group 1 Group 2 Group 3 Discuss rasterisation and vectorisation of digital data with respect to processing data acquired from digital sources. State where each method is most applicable including the advantages and disadvantages. Group 2 Discuss the processes employed in integrating data from different sources. Your discussion should include formats, scale, projections and resampling rasters. Group 3 Discuss the applications of digital cartography as well as the career prospects of a modern cartographer. State some proprietary digital mapping packages and discuss their capabilities and relevance to digital mapping.