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<p>On 2020-08-19 12:17, Andy Townsend wrote:</p>
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<div class="pre" style="margin: 0; padding: 0; font-family: monospace"><span style="white-space: nowrap;">On 19/08/2020 10:11, Stephen Colebourne wrote:</span><span style="white-space: nowrap;">And now I can see Amazon mappers using an iD variant</span><br /><span style="white-space: nowrap;">that doesn't have the offset and moving all the roads as a result:</span><br /><span style="white-space: nowrap;"> <a href="https://osmcha.org/changesets/89549551?aoi=758c7f2b-faca-44e5-acd2-0cb8c33034bd" target="_blank" rel="noopener noreferrer">https://osmcha.org/changesets/89549551?aoi=758c7f2b-faca-44e5-acd2-0cb8c33034bd</a></span><br /><span style="white-space: nowrap;"> <a href="https://www.openstreetmap.org/changeset/89549551" target="_blank" rel="noopener noreferrer">https://www.openstreetmap.org/changeset/89549551</a></span><br /> If that's happening at all, please comment on the changeset explaining the problem. In English urban areas OS OpenData StreetView is a pretty good guide for alignment and if people (especially people doing a lot of editing) are not taking into account different imagery offsets then that's just wrong.</div>
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<div class="pre" style="margin: 0; padding: 0; font-family: monospace">Possibly even better that StreetView imagery is data that has been imported directly from OS, such as OS Boundary-Line for the admin boundaries. This is probably the closest we can get to cm-level accuracy - even though they don't give us the full resolution, the base points such as tripoints where boundaries meet are likely to be pretty damn accurate. I would recommend using these as a kind of calibration point to sanity-check imagery alignment and other data based on less accurate GPS positioning (e.g. from any consumer-grade GPS kit).</div>
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