IFSAR based DEMs directly support three very valuable applications:

1. Formation of the mapping base layer – allowing all other data layers and images (both aerial and satellite) to be more accurate and "map-ready", particularly in hilly or irregular terrain.
2. Add e elevation ("z") data to existing 2D databases and to generate elevation-derived maps (e.g., slope, aspect, runoff).
3. Digital "draping" of imagery (or other mapping data layers) over 3D landscapes, allowing users to visualize data that would otherwise be difficult or impossible to interpret.

The following nationwide data layers can be produced:

1. High accuracy densely populated digital elevation models (DEMs), including both digital surface (DSM) and digital terrain (DTM) models.
2. High-resolution orthorectified radar images (ORIs).
3. Ground Control Points (GCPs) - GCPs are readily identified “surveying points” used in imagery orthorectification and the registration of multiple map layers to a common base. They are key to accurate map layer registration.

Standard Products
Intermap has a standard suite of data products and vertical resolutions available. The three core products are: a digital surface model (DSM), a bare-earth digital terrain model (DTM) and an orthorectified radar image (ORI). These three ‘native’ products provide the basic data layers for GIS and imagery applications.

Figure 3: DSM of Wales, United Kingdom	Figure 4: ORI from NEXTMap Britain

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