Evaluation of panchromatic IKONOS data for mapping

The results of assessment of the planimetric accuracy of 1-meter resolution panchromatic IKONOS data comparing to the topographic map in the scale 1:10,000 are presented. Low precision georeferenced Car terra Geo, 50 m CE90 product of test areas in China was orthorectified in IGiK using Image Station INTERGRAPH and InternationaI Imaging System PRISM VISTA software as well as software elaborated in Chinese Academy of Surveying and Mapping (CASM). Planimetric accuracy of IKONOS data after adjustment with the use of 5 GCP's (taken from the topomap) was: RMSEx = +/- 1.1m and RMSEy = +/- 1.4m. Planimetric accuracy calculated on 18 check points, the X, Y coordinates of which have been also taken from the topomap was: RMSEx = +/-3.5m and RMSEy= +/- 2.5 m. Planimetric accuracy of the orthophotomap generated using IKONOS data and calculated transformation parameters was: RMSEx = +/- 3.7 m and RMSEy = +/- 3.6 m. This accuracy is similar to the planimetric accuracy of the topographic map in the scale 1:10 000. Better accuracy can be achieved by measuring GCP's directly in the field with GPS technique instead of using topomaps. Nevertheless, Сarterra Geo product which is of the lowest horizontal precision out of the entire range of IKONOS products and also the cheapest, can be used for updating topomaps as well as for generating up-to-date digital basemap in modern Geographic Information Systems.