Digital Orthoimagery

Aerial and satellite imagery, in the form of digital orthoimagery, is the foundation for most public and private GIS systems ( NSGIC, Digital Imagery for the Nation, 2006).

Aerial Imagery - A photograph of the earth's surface taken from a platform flying above the surface but not in orbit, usually an aircraft. Aerial photography is often used as a cartographic data source for base-mapping, locating geographic features, and interpreting environmental conditions.

Orthophotograph - An aerial photograph from which distortions owing to camera tilt and ground relief have been removed. An orthophotograph has the same scale throughout and can be used as a map.

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Status of Framework

Montana's most recent orthoimagery is 1-meter NAIP collected in 2005. Compressed county mosaics (CCM) files in NAD 83 State Plane that can either be downloaded or requested on DVD. These data are also available via image services and in uncompressed TIF format upon request from the Base Map Service Center .