Digital elevation model computation with SPOT 5 Panchromatic and Multispectral images using low stereoscopic angle and geometric model refinement

3D information from DTM or DEM is widely used to enhance understanding of satellite images. 3D navigation tools usually include DTM data. Large stereoscopic angles is the common rule since DTM extraction process will then be less sensitive to geometric model accuracy. However, low stereoscopic angle offer valuable evens such as high similarity between the two images of the stereoscopic couple to be correlated. Further more, some satellite such as SPOT5, Formosat, Venus (to be launched) offer native stereoscopy with low B/H value, with CCD arrays staggered in the same focal plane. This paper focuses on the case of SPOT5, where one takes benefit from the low stereoscopic angle between Panchromatic and Multispectral images in order to extract Terrain Model and simultaneously refine the geometric model.