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Sunken GCPs

Hi there!

Im trying to figure out why my marked GCPs are sunk in the model compared to the raw input cords. When my GCPs are imported they look perfect, but after marking them they sink into the model beneath the surface. Im not sure if this is an error, or if the surface of the model is just off. Here are some screenshots: (edit: I can only add 1 photo)

Im using a Phantom 4 RTK and Trimble Catalyst, NTRIP RTK.

Thanks for any help!

Hi @DroneLink,

Pix4Dmapper sets default accuracy of GCPs at 0.02m, but as you are in US feet you’d have to adapt that value so that it is equivalent, i.e. modify the accuracy to 0.066 US feet. This should release the constraint on the GCPs to something more realistic and I would expect the problem you described to disappear.

Let us know if this worked.

Regards,
Pierangelo