3-dimensional position accuracy analysis of maps produced by conventional photogrammetric method: Çaglayan/Erzincan example

In the map production, classical terrestrial methods, photogrammetric method and LIDAR technology are used. Although the most accurate of these methods is classical terrestrial method, it is more convenient to use the photogrammetric method in the production of large areas because of the long working time and the labor force. However, this method also has some disadvantages. The aim of this research is to analyze the accuracy of the photogrammetric method by comparing with the measurement made by the terrestrial methods. In this respect, terrestrial measurements were made at the boundaries of the 1/1000 scale digital map produced by photogrammetric method and analyzed according to the control standards of the existing Large Scale Map and Map Information Production Regulation. The project area is comprised of five districts of Çağlayan municipality in Erzincan. The Cessna 207A aircraft were used for three separate blocks in the project area, one district in each block, a total of three district were measured by terrestrial (classical) methods. Measurements were made by RTK GNSS technique. As a detail point for the control of horizontal coordinates, the building roof corners and walls were measured and compared with the drawing. For height control; measured points' orthometric height which is calculated by interpolation from the local geoid base network and the same measured points' orthometric height which is calculated from the triangular model of drawing were compared. As a result of the comparison, the horizontal coordinate difference was 6 cm on average and vertical coordinate difference was 10 cm on the average. As a result, the differences obtained from the comparison of the measurements made in three different blocks with the drawing were found appropriate according to the control items of BÖHHBÜY. This shows that the digital maps are produced by photogrammetric methods are usable.