City of Helsinki ortho-photographs

Description

The City of Helsinki ortho-photographs are a collection of different ortho-pictures photographed in different years. The entire area of Helsinki is photographed from the air at regular intervals. The descriptions are carried out in such a way that each year a part of the city is photographed. The material series also includes sloping aerial photographs shot in different years as well as false-colour aerial photographs. In recent years, laser scanning has been carried out systematically in connection with aerial imaging. Rectified ortho-pictures are produced from the aerial photographs, which are positioned in the ETRS-GK25 (EPSG:3879) level coordinate system (previously in the City of Helsinki separate coordinate system). The update is annual and the material is produced at different scales. Ortho-pictures have been produced in different precision levels (80 cm, 50 cm, 40 cm, 25 cm, 20 cm and 5 cm/pixel). The most accurate aerial photographs (5 cm) described for the purpose of mapping are described in spring, and the more general aerial photographs describing the surface are usually photographed in the summer. Ortho-air image (orthograph) is a rectified aerial image depicting the ground perpendicular to the air and corrected for a plane map. A diagonal aerial image is a diagonally depicting the surface of the ground. Laser scanning data is a three-dimensional dot-like data describing the surface and objects on the ground, which can be used to produce an exact elevation pattern from the ground. The data is available from WMS and WMTS interface service with levelers Ortho-Air Photo_2019_5cm Ortho-Air Photo_2018_5cm Ortho-Air Photo_2017_8cm Ortho-Air Photo_2017_20cm Ortho-air photo_2016 Ortho-air image_2015_20cm Ortho-air photo_2014 Hazard variant aerial photo_2017_20cm Hazard variant aerial photo_2015_20cm

Resources

Name Format Description Link
0 https://www.avoindata.fi/data/dataset/2b11f6b9-bad2-4710-add3-7217e1cd0610/resource/4db2a5bc-15a9-44d1-9713-03824c8e90f7

Tags

  • ortoilmakuvat
  • laserkeilainkuvat
  • ilmakuvat
  • maasto-ja-maanpeite
  • avoindata.fi
  • maanpeite
  • ei-inspire
  • helsinki

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