Analytical Picture Control Points Survey for Terrain Photogrammetry

Abstract

The structure of the terrain is being constantly changed by continuous geological processes. A corresponding ground plan cartography is a essential basis for a clear representation of the detail of the terrain structure. A terrain photogrametric representation is notable for the sharp measurements and mappings of the irregularities corresponding to the actual detail of the terrain surface.For the measurements and mappings of the terrain surface by mean of a photogrametric survey, the ground and picture control points are inevitable and those are surveyed through triangulation and analytical triangulation respectively. Actually, it is very difficult to get adequate number of ground control points within the changing area whose speed of changes are very fast and also to apply process of analytical aerotriangulation directly to the picture control points survey for the terrain photogrammetry, because a serial pictures like those for aerial photpgrammetry are not available commonly due to topographic conditions. In short, bridging of the models must be considered instead of that of pictures.The authors, here, examined analytical picture control points survey for the terrain photogrammetry experimentally. The base-distance ratio which corresponds to the base-height ratio in the aerial photogammetry is usually very small and it affects largel to the accuracy of the measurements. When forward intersections from the known camera positions are applied, corrections for inherent errors of the phototheodolite and distortion of camera lens must be severely considered.