Accuracy with no Ground Survey Control Points
PhotoSat accuracy when ground surveying control is not possible
PhotoSat produces many satellite surveying projects when the survey data is required before it is possible to get ground survey control. For example, we complete Canadian Arctic satellite surveying projects in mid-winter to enable engineering plans to be prepared before the project areas can be accessed in the spring.
20cm relative accuracy, 3m global accuracy
With no ground survey control, the PhotoSat survey results have a relative elevation accuracy of 20cm in 5km. Points on level bare ground up to 5km apart will have relative elevation accuracy of 20cm.
With no ground survey control, PhotoSat locates the survey data using the orbital data from the satellite photos. This global location is generally accurate to better than 3m in easting, northing and elevation.
Adjusting existing PhotoSat surveys to new ground survey data
When ground survey data becomes available after a PhotoSat survey has been delivered, we can reprocess the satellite photos to adjust the PhotoSat survey to match the new ground survey data. The cost of the reprocessing and reissuing of the PhotoSat survey depends on the size of the survey area. For survey areas of 100km2 the cost is approximately $1,500 US.