The absolute horizontal accuracy of our georeferenced imagery is 0.75m (RMSE) or better. Measurements taken with Nearmap measurement tools are accurate to within 15cm for distances up to 200 meters.
Our HyperCamera aerial photography system captures overlapping photographs along a flight path covering a survey area. Each photograph is tagged with its GPS location.
Our HyperVision technology then triangulates, orthorectifies and stitches these GPS-tagged photographs into a georeferenced photomap with an absolute horizontal accuracy of 0.75m (RMSE) and relative accuracy of 15cm.
We use a combination of GPS positioning, high photo redundancy and triangulation of ground features to ensure this level of accuracy without the use of ground control points.