This paper presents the first results obtained in the evaluation of the planialtimetric accuracy of Digital Surface Models (DSM) and orthoimages generated from a stereo pair of RADARSAT-2 (RST-2) Ultra-Fine (UF) images, polarization C-HH, for an area located in the Curaçá River Valley, State of Bahia, Brazil. For the DSMs and orthoimage generation it was used a mathematical modeling based on the use of Rational Polynomial Coefficients (RPCs), available with RADARSAT-2 Ultra-Fine images. The DSMs and orthoimages were generated without and with one Ground Control Point (GCP). Precise topographic field information acquired from geodetic Global Positioning System (GPS) was used as GCPs for the generation of the DSM and orthoimages and as Independent Check Points (ICPs) for the calculation of the products accuracies. The analysis was performed following the calculations of systematic error (bias) and precision. The test for significant systematic error was based on the Students-t distribution and the test of precision was based on the Chi-squared distribution. The results have shown that the accuracy of the RADARSAT-2 Ultra-Fine DSMs and orthoimages met the requirements for 1:50,000 map (Class A) as requested by the Brazilian Standard for Cartographic Accuracy. Thus, the use of RADARSAT-2 Ultra-Fine images can be considered a promising alternative for detailed topographic mapping in similar environments of the Brazilian territory.Pages: 8129-813
