About the Digital Image Data Base (DIDB) of South Australia

• Orthophotographs
• Georectified Enhanced Satellite Imagery

Documents for download from this site are in PDF format and you will need Adobe Acrobat Reader to view them. The reader is free and can be downloaded from the Adobe website.

Since June 2003, aerial photography is being acquired on a Departmental project basis. The Department for Environment and Heritage (DEH) is looking to enter into cooperative arrangements with Government agencies for the acquisition of aerial photography over areas of common interest. As new imagery becomes available, the DIDB will be updated.

Orthophotographs

The difference between a normal aerial photograph and an orthophoto is that an aerial photograph contains geometric distortions due to aircraft tilt and terrain relief, and therefore does not constitute a true representation of the land. An orthophoto has these distortions removed, and displays the geometric characteristics of a map combined with the image qualities of a photograph.

Environmental Information's (EI) orthophotographs offer a highly accurate visual information source to aid in the understanding, monitoring, forecasting and management of land areas within South Australia. The orthophotos can be integrated with other data layers in a GIS environment to provide a powerful visual analysis tool. Used in this way, the quality and clarity of the image data provides a "complete picture" of the land leading to enhanced urban and environmental planning, and effective asset management.

Digital orthophotos of the built up areas of Adelaide and major country towns (population > 1000) have been produced using our 1:10 000 aerial photography (0.25 metre resolution), whilst the Inner Rural areas surrounding Adelaide are produced using our 1:20 000 aerial photography (0.5 metre resolution). 2.0 metre resolution digital orthophotos using our 1:80 000 scale aerial photography are also available.

Please refer to the following indexes for Orthorectified image coverage over South Australia.

• Ortho-Mosaics over South Australia - Scale: 1:10000 (0.25m) North (440Kb PDF)
• Ortho-Mosaics over South Australia - Scale: 1:10000 (0.25m) South (249Kb PDF)
• Ortho-Mosaics over South Australia - Scale: 1:20000 (0.5m) (275Kb PDF)
• Ortho-Mosaics over South Australia - Scale: 1:40000 (1.0m) (369Kb PDF)
• Ortho-Mosaics over South Australia - Scale: 1:80000 (2.0m) (476Kb PDF)

Please refer to http://www.asdd.sa.gov.au/asdd/ANZSA1027000004.html (new window) for additional information regarding these orthophotographs.

Georectified Enhanced Satellite Imagery

Satellite imagery provides image data that does not necessarily correlate to the known colours of our natural environment, therefore requiring interpretation. Processed to simulate natural colours, however, Enhanced Satellite Imagery (ESI) shows vegetation, lakes, field patterns, towns and other major land cover types in more easily interpreted colours.

Georectified and enhanced satellite imagery is ideal for GIS professionals, catchment and soil groups, teachers, farm managers and regional planners to provide a visual interpretation of the landscape at regional scales.

Enhanced Satellite Imagery consists of Landsat Thematic Mapper (TM) imagery at 25 metre resolution (one-sixteenth of a hectare) and Landsat 7 Enhanced Thematic Mapper (ETM+) imagery at 15 metre resolution. These two levels of resolution are ideal for regional planning, land cover mapping and education projects, and can be integrated with GIS vector datasets such as the Digital Cadastral Data Base.

The Enhanced Satellite Imagery is positioned to the same accuracy as EI's 1:50 000 topographic map series, making the two data sets positionally compatible. ESI is available through ImageMapSA.

Please refer to http://www.asdd.sa.gov.au/asdd/ANZSA1000003008.html (new window) for coverage and revision cycle information regarding the Georectified Enhanced Satellite Imagery.