Since about 1990 image matching is playing a major role in digital photogrammetry. Current  tools of image matching allow the generation of high quality point clouds for Digital Terrain Models (DTM) and Surface Models (DSM), which is challenging the established Airborne Laser Scanning (ALS) technology. The imagery provides a much higher planimetric resolution and can provide much denser point clouds. Still the problems of vegetation and the problems of occlusions in urban areas, like also in ALS, need to be addressed.

The new technolgy of multi-image matching and DSM generation exploits the high quality image data and high overlap when imaging with modern digital cameras:
Results on the highly demanding DSM generation in an open pit coal mine are presented and the potential for high quality change detection discussed.

Similarities between filtering point clouds from image matching and that of ALS are analysed. RGB and NIR channels of digital cameras are used to improve the classification of point clouds.
Finally an application using stereo satellite data demonstrates the potential for automated DSM generation in regions, where no aerial flights are available.