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<div style="direction: ltr;">You might be in the old French System as I recall. Check out my Grids & Datums from PE&RS, July 2002.</div>
<div style="direction: ltr;">C. Mugnier</div>
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<div id="divRplyFwdMsg" dir="ltr"><font face="Calibri, sans-serif" style="font-size:11pt" color="#000000"><b>From:</b> PROJ <proj-bounces@lists.osgeo.org> on behalf of Jelmer Baas <Jelmer.Baas@speerit.nl><br>
<b>Sent:</b> Friday, February 7, 2020 9:00:34 AM<br>
<b>To:</b> proj@lists.osgeo.org <proj@lists.osgeo.org><br>
<b>Subject:</b> [PROJ] Proper projection system for Aruba</font>
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<p class="x_MsoNormal"><span lang="EN-US">Hello,</span></p>
<p class="x_MsoNormal"><span lang="EN-US"> </span></p>
<p class="x_MsoNormal"><span lang="EN-US">I’m trying to convert coordinates from what seems to be a custom projection system in Aruba, without much luck.</span></p>
<p class="x_MsoNormal"><span lang="EN-US"> </span></p>
<p class="x_MsoNormal"><span lang="EN-US">In their drawings, they have data around 3000, 18000. Whatever existing projection system I use (EPSG 24819, EPSG 32619), I end up at a completely different location.</span></p>
<p class="x_MsoNormal"><span lang="EN-US"> </span></p>
<p class="x_MsoNormal"><span lang="EN-US">For example:</span></p>
<p class="x_MsoNormal"><span lang="EN-US">echo 2936 18088 | cs2cs +proj=utm +zone=19 +ellps=intl +towgs84=-216.408,279.243,-203.231,-8.56912,40.8756,-12.5593,15.8909 +units=m +to +proj=webmerc +datum=WGS84</span></p>
<p class="x_MsoNormal"><span lang="EN-US">-8178296.58 17850.76 22.52</span></p>
<p class="x_MsoNormal"><span lang="EN-US"> </span></p>
<p class="x_MsoNormal"><span lang="EN-US">echo 2936 18088 | cs2cs +proj=utm +ellps=intl +towgs84=-216.408,279.243,-203.231,-8.56912,40.8756,-12.5593,15.8909 +units=m +to +proj=webmerc +datum=WGS84</span></p>
<p class="x_MsoNormal"><span lang="EN-US">-830835.88 16729.91 101.08</span></p>
<p class="x_MsoNormal"><span lang="EN-US"> </span></p>
<p class="x_MsoNormal"><span lang="EN-US">This is way outside the expected area. In 3857, the data should be somewhere between</span></p>
<p class="x_MsoNormal"><span lang="EN-US">-7800000, 1417000</span></p>
<p class="x_MsoNormal"><span lang="EN-US">-7777000, 1393000</span></p>
<p class="x_MsoNormal"><span lang="EN-US"> </span></p>
<p class="x_MsoNormal"><span lang="EN-US">I do have the attached “.gtf” files, but I’m unsure how to apply this in proj. Is the above string correct? What am I missing?</span></p>
<p class="x_MsoNormal"><span lang="EN-US"> </span></p>
<p class="x_MsoNormal"><span lang="EN-US">Any help would be greatly appreciated.</span></p>
<p class="x_MsoNormal"><span lang="EN-US"> </span></p>
<p class="x_MsoNormal"><span lang="EN-US">Regards,</span></p>
<p class="x_MsoNormal"><span lang="EN-US">Jelmer Baas</span></p>
<p class="x_MsoNormal"><span lang="EN-US"> </span></p>
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