ABSTRACT
By far the largest amount of base data held in most geospatial databases has been acquired by or derived from airborne cameras and laser scanners mounted on manned airborne platforms, with the support of the appropriate photogrammetric technologies. Besides the traditional vector map data that can be extracted from the resulting aerial photographs and the stereo-models that are formed from them, data from these airborne sensors can also produce newer geospatial products such as orthophotographs and 3D surface or terrain models. Although other platforms and technologies have been introduced for data collection over the last 50 years, airborne digital mapping still holds sway as the dominant method of acquiring the base topographic data on which geospatial databases are built.
