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Offset when merging arbitrary and coordinate projects

 I’m kind of new to Pix4d, could someone explain why this happens when I combine oblique images taken from a drone and terrestrial images taken by a Gopro please? I can’t work it out. 

 

Hi Adrian,

You need to follow the instructions of the following tutorial Merging Projects

(Adding common Manual Tie Points at the individual projects before creating your merged project should solve your issue :slight_smile: )

Let us know if this does not help!

Hi thanks for the reply. I have had a number of successful attempts when merging projects from the same source (i.e drone) using a number of mtp’s. This project also has a number of matching mtp’s before the merge and the point cloud is correct to that effect. However there is this large discrepancy between what I think is the actual camera positions to the calculated positions. To be honest I can live with that if there is a way to recenter the point cloud as at the moment when opening the project the viewer focuses on blank space.

Oh! I see! the original camera position is very far (blue dots in the rayCloud), because the software moved the geolocated images to the non geolocated ones (instead of the opposite). Is that the case?

To recenter your model, just click on an en element on the left sidebar and then click the Focus on Selection button:

Yes thats a far better way of explaining it than my version! Is it possible to make the software do the reverse? Thanks for the recenter tip.

Hi Adrian, 

you could try to give a higher weight to your images’ coordinates by setting them as more accurate than the default 5 and 10 meters. You could set for example the accuracy to _0.5 _meters :

If your camera coordinates are not very accurate, this could lead in other problems, but it is worth a try!