Ground Control
Last updated
Last updated
Ground control points (GCPs) can be used for accuracy assessment, accuracy reporting, and data adjustment. To import GCPs into a project, use File->Open to open a CSV file - SpatialExplorer will automatically assume that a CSV contains GCP information. You will then need to specify the coordinate system of the GCPs as well as the column assignments:
GCPs are assigned via their Type attribute as either Check, Control, or Unused points:
Check and Control points are generally collected at the same time, using the same methodology.
Control points are used for data adjustments, whereas Check points are used for accuracy reporting. Control points appear orange in the main view, while check points appear blue.
GCPs utilized for data adjustments should not be used to validate the accuracy of the data product.
Ensure the Coordinate Reference System (CRS) is properly configured to match the CRS that the GCPs reference. For configuring the CRS menu, refer to Coordinate Reference System window.
Visually verify the GCPs are properly georeferenced:
You can find more information on the principles of ground control usage and collection here:
