Accuracy assessment of digital elevation model derived from Göktürk-1 satellite images

These days, when technology is developing fast, diffirent kind of systems have taken place in connection with the purpose of reaching and processing data properly. We can get high resolution images of the Earth with no restrictions on satellite Göktürk-1 a using to the giant steps that our country has taken so far. Also, thanks to the transfer of our experiencess in the field of remote sensing our data has turned into the high added value products. Digital elevation model (DEM) is a numerical model that describes the surface of a terrain in three dimensions with the help of mathematical rules and is shown using the elevation information of the terrain. Satellite images are frequently preferred in DEM production due to advantages such as economy, less need for manpower, production speed and ease of access to data. Thanks to the improvements made on the RPC (Rational Polynomial Coefficients) model, which is one of the auxiliary parameters of satellite images, data with high positional accuracy can be obtained today compared to past times. In this thesis study, different data were provided to investigate the vertical accuracy of the DEM data produced from Göktürk-1 satellite images. In this context, while point-based vertical accuracy assessment was carried out with Ground Control Points (GCP) data, vertical accuracy assessment based on surface analysis was carried out with Worldview-2 DEM data with the help of DSM data obtained from HGM. In the analysis of Göktürk-1 DEM data according to Ground Control Points (GCP); The accuracy of the DEM data produced using 1 GCP is 2.51m at the 95% confidence level (LE95), while the accuracy of the DEM data produced with RPC is 5.48m according to LE95. In the other analysis, Göktürk-1 DEM and Worldview-2 DEM data, which have a common coverage area, were made together with DSM5 data with vertical positional accuracy of ±3 m at 90% confidence interval (LE90) obtained from HGM. According to the findings obtained, in the vertical positional accuracy assessment; While Worldview-2 DEM and Gkt-1 DEM give approximate results, it was analyzed that there was a noticeable improvement in the DEM data produced using GCP compared to the DEM data produced with the help of RPC.