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Set Phi when processing terrestrial images?

I’m doing some terrestrial work with a Lumix ZX-40 (18 MP, GPS enabled) camera.

When I do initial processing using the 3D model template I’m still getting some images with a calculated position pointing downwards.

When I take the photos I use an on screen display that shows whether I’m level and pointing up or down. Since I take my photos generally pointing down about 10 degrees from the horizon, would it help to set Phi (roll, or rotation about the Y axis) to 80? I assume Phi is in degrees and nadir based.

Basically I want to help P4D out in the initial stages.

Hi David, 

Here is how Pix4D defines Omega, Phi and Kappa:

Accurate geolocation and data for all three angles would need to be available for it to be taken into account during processing. If this is available, the “Accurate Geolocation and Orientation” option in Process > Processing Options > 1. Initial Processing > Calibration, could be used. However, it might be difficult to achieve for ground based projects.

If we correctly understood, there are only a few images that are not oriented in the right direction. In this case, we would suggest to add a few Manual Tie Points (MTPs) and to Process > Reoptimize the project, which should help the images to correctly align. More here:

In addition, we would also check that there is enough overlap between the images (at least 75% frontal and 60% side overlap). Maybe increasing the overlap could help the reconstruction, as more matches might be found between the images wrongly oriented and the others. 

If all images were oriented in the wrong direction, we would add an orientation constraint: