<html>
  <head>
    <meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
  </head>
  <body>
    <p>Hello Andrew, hello everyone else.</p>
    <p><br>
    </p>
    <p>I've not done a "big revert" yet; I've concentrated on trying to
      work out how to do that without adversely affecting everyone
      else's work, and as I'm sure you've guessed, it's been more of a
      background job rather than originally intended.  Despite warning
      of a "potential hole appearing in the data in West London in a few
      days time" back in April last year, I now hope that I'll be able
      to restrict changes to problem keys only, and only deal with
      problem imagery where specific problems have been reported, like
      <a class="moz-txt-link-freetext" href="https://www.openstreetmap.org/way/144667839">https://www.openstreetmap.org/way/144667839</a> in the example below
      (note that <a class="moz-txt-link-freetext" href="https://www.openstreetmap.org/way/996697879">https://www.openstreetmap.org/way/996697879</a> in the same
      changeset matches the claimed Bing imagery).</p>
    <p><br>
    </p>
    <p>Best Regards,</p>
    <p><br>
    </p>
    <p>Andy<br>
    </p>
    <p><br>
    </p>
    <p><br>
    </p>
    <div class="moz-cite-prefix">On 29/01/2023 18:01, Andrew Hain wrote:<br>
    </div>
    <blockquote type="cite"
cite="mid:AM8P250MB0012182D3CC9B58F2B8C492DE6D29@AM8P250MB0012.EURP250.PROD.OUTLOOK.COM">
      <meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
      <style type="text/css" style="display:none;">P {margin-top:0;margin-bottom:0;}</style>
      <div style="font-family: Calibri, Helvetica, sans-serif;
        font-size: 12pt; color: rgb(0, 0, 0); background-color: rgb(255,
        255, 255);" class="elementToProof">
        Is the mapping in West London now in a state where mappers can
        build on it without risking their edits getting lost?</div>
      <div style="font-family: Calibri, Helvetica, sans-serif;
        font-size: 12pt; color: rgb(0, 0, 0); background-color: rgb(255,
        255, 255);" class="elementToProof">
        <br>
      </div>
      <div style="font-family: Calibri, Helvetica, sans-serif;
        font-size: 12pt; color: rgb(0, 0, 0); background-color: rgb(255,
        255, 255);" class="elementToProof">
        --</div>
      <div style="font-family: Calibri, Helvetica, sans-serif;
        font-size: 12pt; color: rgb(0, 0, 0); background-color: rgb(255,
        255, 255);" class="elementToProof">
        Andrew<br>
      </div>
      <hr style="display:inline-block;width:98%" tabindex="-1">
      <div id="divRplyFwdMsg" dir="ltr"><font style="font-size:11pt"
          face="Calibri, sans-serif" color="#000000"><b>From:</b> Andy
          Townsend <a class="moz-txt-link-rfc2396E" href="mailto:ajt1047@gmail.com"><ajt1047@gmail.com></a><br>
          <b>Sent:</b> 18 April 2022 12:44<br>
          <b>To:</b> Talk Gb <a class="moz-txt-link-rfc2396E" href="mailto:talk-gb@openstreetmap.org"><talk-gb@openstreetmap.org></a><br>
          <b>Subject:</b> [Talk-GB] Potentially incompatible edits in
          West London</font>
        <div> </div>
      </div>
      <div class="BodyFragment"><font size="2"><span
            style="font-size:11pt;">
            <div class="PlainText">Hello - especially to mappers in
              London.  Andy from OSM's Data Working
              <br>
              Group here.<br>
              <br>
              There's been a suggestion that mapper that has been very
              active in West <br>
              London* <a
                href="https://www.openstreetmap.org/user/Mikhail1412"
                moz-do-not-send="true" class="moz-txt-link-freetext">https://www.openstreetmap.org/user/Mikhail1412</a>
              has been using
              <br>
              various sources that aren't compatible with OSM. Attempts
              to contact the <br>
              mapper via <br>
              <a
href="http://resultmaps.neis-one.org/osm-discussion-comments?uid=2055614"
                moz-do-not-send="true" class="moz-txt-link-freetext">http://resultmaps.neis-one.org/osm-discussion-comments?uid=2055614</a>
              have
              <br>
              mostly been unsuccessful, although a local mapper has
              managed to get <br>
              replies to some private messages (which unfortunately do
              also suggest <br>
              that they're using incompatible sources).  It has been
              suggested that <br>
              <a href="https://www.openstreetmap.org/user/Mik1412"
                moz-do-not-send="true" class="moz-txt-link-freetext">https://www.openstreetmap.org/user/Mik1412</a>
              is another account by the
              <br>
              same person.<br>
              <br>
              Attempts by the DWG to get the mapper to interact with the
              community <br>
              have failed: <a
                href="https://www.openstreetmap.org/user/Mikhail1412/blocks"
                moz-do-not-send="true" class="moz-txt-link-freetext">https://www.openstreetmap.org/user/Mikhail1412/blocks</a>
              ,
              <br>
              hence a "block until they engage with us" message at <br>
              <a href="https://www.openstreetmap.org/user_blocks/5919"
                moz-do-not-send="true" class="moz-txt-link-freetext">https://www.openstreetmap.org/user_blocks/5919</a>
              .<br>
              <br>
              I had hoped that we'd be able to revert and redact certain
              classes of <br>
              data only (see e.g. comment on <br>
              <a
                href="https://www.openstreetmap.org/changeset/113072980"
                moz-do-not-send="true" class="moz-txt-link-freetext">https://www.openstreetmap.org/changeset/113072980</a>
              ).  However, the
              <br>
              problematic changes include geometric changes too - it has
              been said <br>
              that the latest change to <a
                href="https://www.openstreetmap.org/way/144667839"
                moz-do-not-send="true" class="moz-txt-link-freetext">https://www.openstreetmap.org/way/144667839</a>
              <br>
              (see the top-right corner of <br>
              <a
                href="https://overpass-api.de/achavi/?changeset=113007152"
                moz-do-not-send="true" class="moz-txt-link-freetext">https://overpass-api.de/achavi/?changeset=113007152</a>
              ) isn't possible
              <br>
              based on imagery available to OSM because of tree cover. 
              That edit is <br>
              unlikely to be based on survey as the mapper concerned
              apparently hasn't <br>
              been in London since late 2019 (due to the pandemic
              etc.).  Some other <br>
              changes seem to match Google Street View and not a more
              recent survey.<br>
              <br>
              It therefore looks like we'll have to revert (and likely
              redact) most or <br>
              all of this mapper's changes since the beginning of 2020,
              unless we get <br>
              a reason not to from a reply to <br>
              <a href="https://www.openstreetmap.org/user_blocks/5919"
                moz-do-not-send="true" class="moz-txt-link-freetext">https://www.openstreetmap.org/user_blocks/5919</a>
              .  I'm sending this
              <br>
              message for a few reasons:<br>
              <br>
              * to encourage mappers in West London to comment on this
              user's <br>
              changesets, both where the data appears not to be based on
              sources <br>
              available to OSM but also where it can be validated by
              e.g. survey.  I <br>
              don't expect that you'll get a reply, but those comments
              will be <br>
              extremely useful to us and to everyone else in the area.<br>
              <br>
              * to give everyone a chance to tell me if I've got
              anything wrong <br>
              (please reply on this list if that's the case).<br>
              <br>
              * to give everyone a bit of a warning of a potential
              "hole" appearing in <br>
              the data in West London in a few days time.<br>
              <br>
              I won't start any wide-scale revert for a week or so to
              give the mapper <br>
              concerned yet another chance to reply.  I have already
              reverted (and <br>
              redacted) some changes in <br>
              <a
                href="https://www.openstreetmap.org/changeset/115296538"
                moz-do-not-send="true" class="moz-txt-link-freetext">https://www.openstreetmap.org/changeset/115296538</a>
              where there were
              <br>
              specific reports about individual pieces of data.<br>
              <br>
              Best Regards,<br>
              <br>
              Andy<br>
              <br>
              * more recently the same mapper has been active in France
              - I've also <br>
              asked them for the sources of their edits there.<br>
              <br>
              <br>
              <br>
              _______________________________________________<br>
              Talk-GB mailing list<br>
              <a class="moz-txt-link-abbreviated" href="mailto:Talk-GB@openstreetmap.org">Talk-GB@openstreetmap.org</a><br>
              <a href="https://lists.openstreetmap.org/listinfo/talk-gb"
                moz-do-not-send="true" class="moz-txt-link-freetext">https://lists.openstreetmap.org/listinfo/talk-gb</a><br>
            </div>
          </span></font></div>
    </blockquote>
  </body>
</html>