Automatic Aerial Triangulation – Report of a Large Project under Difficult Conditions

The Provincia Autonoma di Bolzano – Alto Adige commissioned the bidding group GEOSIGMA s.r.l., GEOMATICA s.r.l. and Ingenieurgemeinschaft Vermessung AVT-ZT GesmbH to produce a GIS-data base of parts of their province. It was demanded to create topographic data for technical base map in the scales 1:5.000 and 1:10.000. For the data acquisition an existing photo flight of about 2.500 images was used. Following, the most critical parameters of the specific block adjustment are given: An alpine and topographically very challenging region with height differences up to 2.000 m within one image. The photo flight mission was carried out over a period of about 4 months. 4 different aerial cameras have been used for taking the images. The whole area is covered by East-West-flight lines, which are divided in several sub-strips. Additional strips were flown along the valleys in lager scales. Thus a very inhomogeneous image pattern exists. Geometric problems appeared in some of the scanned images. This paper presents the realisation of the automatic aerial triangulation using INPHO-software, the gained results and the corresponding quality control.