Rentsch, H (1982): Orthophotokarte Vernagtferner 1979 in jpg-Format (54 MB). doi:10.1594/PANGAEA.771301, Supplement to:Rentsch, Hermann (1982): Die Orthophotokarte Vernagtferner 1979. Zeitschrift für Gletscherkunde und Glazialgeologie, 18(1), 85-91, hdl:10013/epic.38396.d001
For the production of the orthophoto map Vernagtferner 1979, scale I: 10000, photographs of the flight "Hintereisferner 1979" were used, which have been found to be very suitable for differential rectification. Control points were determined before the flight took place. The processing of nine stereopairs was carried out on an analytical plotter. Simultaneously with the on-line plotting of the contour lines the reference data for the computation of the profiles for the differential rectification were recorded. The orthophoto map was covered by four aerial photographs. A smooth data transfer was ensured because the same computer was used for the data acquisition and the differential rectification. Two printing originals were prepared, one for the outline drawings with contour lines and another for the orthophoto. The print was done in black for the two copies. The data acquisition, the computation of the scanning profiles for the othoprojector and the procedure of the differential rectification are described. The reason for the use of on-line drawn contour lines is explained. Further applications, also for digital contour lines, are introduced. Possibilities for the achievement of high photo quality during the reproduction are discussed.