Welcome back to 3Dsurvey tutorials.
We’ll talk about the correct way of setting your ground control targets before the flight. We need them for accurate 3D data in order for 3Dsurvey to automatically process model orientation.
When you buy 3Dsurvey software it comes with 10 ground targets made from durable plastic to cope with your everyday tasks.
It is very important to set the targets properly to achieve end results with land surveying accuracy. I always print a Google map and asign approximate spots of control targets before leaving the office. There are two rules:
First; try to place ground control targets as homogeneously as possible across the selected area. Here are examples of correct and incorrect placements.
Second; always make sure that your area is within the boundaries of ground control points. Here’s the example; we have the area coloured in blue, the correct placement of ground control points is on the left and the incorrect on the right.
The minimum number of ground control points is 3 but you should always use more to have them serve as redundant measurements. To finish, measure ground control targets with GPS or a total station and start your flight.