The Institute of Photogrammetry has developed a peripheral system for the automatic derivation of digital terrain models for the analytical plotter Kern DSR 15; this project is carried out in close collaboration with Leica AG. The principal component of the system is a parallel processor based on Transputer technology. The correlation process itself runs off-line on the Transputer system according to the Multi-Templet-Matching procedure. In a second phase, the results of the image correlation are smoothed during a process which also filters out the terrain obstacles. This process runs completely automatically. The analytical plotter DSR 15 is used for the digitalization of aerial photographs and for the control and possible revision of digital terrain models; consequently, the data are integrated into an information system. The results of the image correlation can also be used for the production of digital orthophotos. The procedure has been conceived for large-scale photographs (-1:5000); according to various precision analyses, a height precision smaller than 0.1% of the flying height can be obtained.