DEM generation by means of new digital aerial cameras

Abstract

Based on practical experiences with the first generation of digital cameras the impact of four new digital aerial cameras on the DEM generation is estimated. The cameras are evaluated with respect to elevation accuracy, area coverage and image quality. In the derived formulae for the absolute accuracy of elevations a camera factor is applied, which summarizes several features in one number. The produced graphs show the potential of the new cameras regarding the relative and absolute accuracy of automatically derived elevations. For better absolute elevation accuracy the increase of the base/height ratio and of the resolving power of lenses are more important than the reduction of the pixel size. Improvement of the elevation accuracy by means of multi-ray photogrammetry is discussed.