Potential applications

Meeting vital mapping needs

Traditional maps cover no more than 44 per cent of Earth's landmasses, so the need for basemaps is huge indeed. What is more, nations now investing increasingly in digital geographic information want to update their databases quickly. SPOT 5 will meet mapping requirements at scales of 1:50 000 up to 1:25 000-something that has proved hard to achieve with first-generation satellite data.

SPOT 5, particularly its 2.5-metre black-and-white acquisition mode, offers the ability to map at new scales for a broad range of applications. SPOT 5's two key assets are:

• Accurate and detailed observation of terrain features
• Coverage of vast territories.

2.5-metre black-and-white data from SPOT 5 are well suited to generating or updating medium-scale databases (such as IGN's BD CARTO®) of regions for which accurate maps are available.

 

 

This example shows the level of detail achievable using SPOT 5 black-and-white data with 2.5-metre resolution.
SPOT 5 data even exceed operational requirements for updating map databases of this type of landscape.

 

An unrivalled tool for producing and updating topographic maps in developing countries.
In developing countries where maps are often out of date and vast areas need to be covered, 2.5-metre black-and-white data from SPOT 5 are ideal for generating high-quality map products at scales of 1:50 000 up to 1:25 000.

 

Defence simulation and training
Simulation and training applications call for accurate and realistic 3D databases, which can be generated from SPOT 5 stereopair imagery.

3D databases for simulation applications can be generated with SPOT 5 2.5-metre black-and-white data used to derive:
- digital elevation models (DEMs)
- orthoimages
- man-made features extracted by photogrammetry.

Trials conducted with simulated SPOT 5 data show that extraction of man-made and planimetric features using photogrammetric techniques is of great value for rehearsing missions, where features need to be represented in three dimensions as realistically as possible.

3D superstructures extracted by photogrammetry. Elevation accuracy is sufficient to meet application needs.

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HRG instrument (High Resolution Geometric) - Finer ground resolution in black-and-white mode: 2.5 metres and 5 metres (instead of 10 metres). - Like all their predecessors, each SPOT 5 instrument covers a 60-kilometre swath - Oblique viewing makes it possible to revisit areas of interest frequently. - Finer resolution in colour mode: 10 metres (instead of 20 metres) HRS instrument (High Resolution Stereoscopic) designed specially to acquire wide-area DEMs - SPOT 5's dedicated HRS instrument provides stereoscopic imaging capability along the satellite track. - Panchromatic band offers spatial resolution of 10 metres. - The imaging swath centred on the satellite ground track is 120 kilometres, and maximum scene length is 600 kilometres. - Elevation accuracy of DEMs generated from HRS images: . Relative: 5 to 10 metres . Absolute: 10 to 15 metres

 

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References

SPOT 5 Preparatory Programme

• Study of the use of SPOT 5 Supermode data for generating 3D simulation and training databases - Thales.
• Evaluation of the use of SPOT 5 Supermode data for updating map databases - IGN.

Potential applications SPOT 5's wide swath and the fine detail of 2.5-metre black-and-white imagery offer significant advantages over the current generation of remote sensing instruments for mapping applications. SPOT 5 will serve applications in the market for regular topographic surveying, which has traditionally been the preserve of aerial photography. SPOT 5 data are a precious source of information in developing countries where map coverage is most often incomplete and out of date, making it possible to generate satellite imagemaps at scales of 1:50 000 and 1:25 000, and to update existing maps.