SfM reconstruction flipped w.r.t Z axis about openmvg HOT 3 CLOSED

Could be that there is a ambiguity if all your GPS prior are in the same 2D plane?

• are you GPS prior on a plane?
• try with more distributed GPS (that would not fit in a 2D plane)

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Thanks Pierre for the reply.
That's the full acquisition:

The GPS priors are not on a plane. Note that w.r.t the prior, it's custom code, where the priors are directly expressed in a right-handed local reference frame with Z pointing "down" (Z decreases as the drone takes off). I've tried reverting the coordinates system with Z up, but that didn't make a difference. Prior and reconstruction are flipped.
I understand why there could be an ambiguity, but what puzzles me is that no matter what kind of SfM engine I use or initial pair I use, the reconstruction is always flipped. I would have expected a some randomness between flipped vs non-flipped reconstruction if it's an ambiguity.
I've tried Incremental engine with initialization from the location where the craft turns (more random movements) - see pic - but still, reconstruction is flipped.

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Ah, actually, I made a mistake and was reverting X/Y.
Sorry for trouble, but it's working as expected now.
Thanks again!

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