Characteristics of very high resolution optical satellites for topographic mapping

Abstract

The ground resolution of optical satellites now overlaps with the ground resolution of aerial images. The radiometric and geometric quality of the satellite images can be compared with original digital aerial images and is better as corresponding analog photos. Important parameters for the operational handling of the very high resolution satellite images as imaging capacity, revisit time and rotation speed, important for getting stereo pairs and the flexibility of imaging of different areas, and effective image resolution are shown in detail. The reason for changed spectral range of GeoEye-1 and WorldView-2 against preceding systems is explained with its consequences to pan-sharpening. Scene orientation today is not a problem, so approximations are not justified anymore. With the improved possibility of stereoscopic coverage within the orbit, digital elevation models operationally can be generated. For some types of automatic image matching epipolar images are required. Based on images projected to a plane with constant height or even a rough height model a rotation of the satellite images to the base direction is satisfying as quasi epipolar images. The remaining discrepancies against theoretical strict epipolar images are estimated.