3D measurement data NW

The 3D measurement data (3DM) from laser scanning describe the terrain and surface through irregularly distributed georeferenced elevation points. The point density in NRW is an average of 4 to 10 points per square meter. Especially in forest areas, the point density can increase significantly. Aircraft-assisted laser scanning (ALS) is used as a detection method in North Rhine-Westphalia. The 3DM contains all reflections of the ALS in a classified measuring point cloud. The OGC standard LAS is used as the data format in version 1.2 in Point Data Record Format 1 (PDRF 1). The data is provided in compressed LAS format (LAZ) via the download portal. In 2017, the data collection was switched to the so-called Full Wave Laser Scanning. In addition to all reflections for each laser pulse, additional information is collected here. Since no full wave laser scanning has yet been recorded, data content and the number of point classes in NRW still differ. The WMS-Viewer “DHM Overview” provides information about the availability and up-to-dateness of the 3D measurement data. From these raw data, the 3D measurement data, digital terrain models with regular grid width are calculated. Geobasis NRW provides DGM1 as part of its statutory mandate (see DGM1), where the number in the designation indicates the lattice width (i.e. a grid width of 1 m for DGM1).