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cyberaxyesterday at 9:56 AM1 replyview on HN

OSM uses a hundred nanodegrees as the grid resolution ( https://github.com/openstreetmap/OSM-binary/blob/32c3e921665... ). It gives a bit more than 1cm precision.

> The point I'm trying to make is that there are more important sources of error before you get to tectonic movement and GPS drift...

You can absolutely measure tectonic drift on the OSM maps! They've existed long enough for it to be actually significant in a lot of places if you download the old data.

This also comes up all the time when trying to overlap data from local agencies onto the OSM maps. You end up with parcel boundaries visibly off.


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phoronixrlyyesterday at 11:33 AM

> OSM uses a hundred nanodegrees as the grid resolution

As I said, 7-digit precision.

> You can absolutely measure tectonic drift on the OSM maps! They've existed long enough for it to be actually significant in a lot of places if you download the old data. > > This also comes up all the time when trying to overlap data from local agencies onto the OSM maps. You end up with parcel boundaries visibly off.

Yeah, assuming the person who added the features you're observing as 'visibly off' did not use 1-meter Bing imagery with a 10-meter offset...

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