Historical Digital Orthophotos NW

Orthophotos are high-resolution, distortion-free, true-to-scale images of the Earth’s surface. They are produced by photogrammetric methods in knowledge of the orientation parameters and with the addition of a digital terrain model from aerial images, which are available as vertical images. Orthophotos become historical as soon as they are replaced by DOP of the current flight. Over the years, orthophoto production has been constantly adapted to changing needs and technical progress. Historical orthophotos can therefore differ in individual characteristic features. For example, there have been colored orthophotos only since 1998, but there are also significant differences in soil resolution (10 cm/pixel since 2 014.20 cm/pixel from 2008 to 2 013.30 cm/pixel from 1996 to 2 007.40 cm/pixel before 1996). Orthophotos in the period since 1996 have been produced completely digitally, orthophotos from the previous years were created by scanning analog half-tone prints from the DGK5 archive.