Orthophotos — current

The orthophotos are a geo-based database specially produced for Dresden (basic map). This depicts the urban area of the state capital Dresden with the help of equal, georeferenced aerial images in a soil resolution of 20 cm. Based on the surveying survey flights carried out almost annually, the original contains comprehensive material of georeferenced aerial images (perpendicular images) with 60 % longitudinal and 30 % cross cover. Initially used as a basis for photogrammetric stereo evaluation, these images are suitable after a differential equalisation as an information layer in a GIS, WMS, etc.. These so-called orthophotos are largely free of location errors (resulting from the shooting process and the elevation movement of the site) and exhibit the same geometric properties of a map — supplemented by the pictorial information of a photograph. As a rule, several orthophotos are assembled into one or more orthophotomosaiks, depending on whether a leaf-cut-free or tiled storage is desired or required.