How worried should I be about low compass precision?

I’ve discarded a few thousand captures, because on the map preview they appeared to have the wrong compass direction. Some of the misaligned photos remained, though, and I now see that they have been corrected.

See this capture, for example:

It was captured (incorrectly) as pointing north-east:


But after clicking it on the map, I see that Mapillary has shifted its position and direction to a proper one:


I’m starting to think I shouldn’t have deleted those pictures… And in the meantime shifted to an OpenCamera+Termux workflow on Android.

How worried should I be about wrong compass data on my captures? Is it safe to disregard the issue of compass misalignment completely and just upload all the pics?

In my experience with process/upload via the tools, it is possible to use either the compass direction from EXIF/nmea or just allow (or force) it to be calculated from one frame to the next. The parameter being --interpolate_directions

I do not know how the smartphone code does this, but given your experience it would seem that forcing is enabled for processing, but not whilst in preview. There are then only two concerns, that the first or last frame in a sequence has a direction error or the camera is not pointing in the direction of travel.

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