ACCURACY
30cm PhotoSat Surveying Accuracy
To achieve 30cm survey accuracy, PhotoSat needs at least 3 ground survey control points for areas up to 100km².
PhotoSat routinely produces survey data accurate to 30cm in elevation on mine sites and oil and gas projects.
PhotoSat processing with no ground survey points produces 20cm relative and 3m global survey accuracy
PhotoSat applies a number of corrections to the stereo satellite photos prior to applying the ground survey data. These preliminary corrections usually bring the relative PhotoSat survey accuracy to 20cm in elevation over horizontal distances of 10km. The global accuracy prior to applying ground survey data is usually better than 3m in x, y and z.
PhotoSat processing using three ground survey points per 100km2 produces better than 30cm survey accuracy
PhotoSat routinely achieves better then 30cm absolute survey accuracy using stereo WorldView-1, 2 or 3 satellite photos and Pleiades 1A and 1B Satellite photos when using as few as three ground survey points per 100 km2. We believe that 30cm survey accuracy is a conservative specification. In most cases the PhotoSat survey accuracy is much better than 30cm.
For instance, the PhotoSat survey using WorldView-3 over PhotoSat’s California test area is accurate to 13cm using a single control point. To see the WorldView-3 California test area accuracy study click here.
PhotoSat absolute survey accuracy of 20cm is achieved using ten ground survey points per 100km2. This is discussed in the 20cm accuracy page. Better than 15cm absolute survey accuracy is achieved with 100 ground survey points per 100km2. This is discussed in the 15cm accuracy page.
1.wv1-garlock-3gcp-20cm-rmse.jpg-Caption:”WorldView-1 PhotoSat survey over the California test area using three survey points to achieve elevation surveying accuracy of 20cm RMSE. The survey accuracy was checked with 7,343 check points.”
2.wv3-eritrea-5gcp-19cm-rmse.jpg-Caption:”198 km2 WorldView-3 PhotoSat survey over the Eritrea test area using five survey points to achieve elevation surveying accuracy of 19cm RMSE. The survey accuracy was checked with 1,803 check points.”