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<th valign="BASELINE" nowrap="nowrap" align="RIGHT">Subject:
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<td>some help with cm-level GRS80 to WGS-84 transformation?</td>
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<td>Wed, 19 Jan 2022 11:28:24 -0700</td>
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<th valign="BASELINE" nowrap="nowrap" align="RIGHT">From: </th>
<td>Joseph Boardman <a class="moz-txt-link-rfc2396E" href="mailto:boardman@aigllc.com"><boardman@aigllc.com></a></td>
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<th valign="BASELINE" nowrap="nowrap" align="RIGHT">To: </th>
<td><a class="moz-txt-link-abbreviated" href="mailto:proj@lists.osgeo.org">proj@lists.osgeo.org</a></td>
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<p>Dear Proj Experts,</p>
<p>I'm a remote sensing geophysicist with experience in geodesy
and mapping.</p>
<p>Right now I'm struggling trying to get a high-accuracy proj
command to convert from GRS80 to WGS-84 at the cm level.</p>
<p>Any clues? cs2cs is not doing it.<br>
</p>
<p><span style="color: rgb(29, 28, 29); font-family: Slack-Lato,
appleLogo, sans-serif; font-size: 15px; font-style: normal;
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255, 255); text-decoration-thickness: initial;
text-decoration-style: initial; text-decoration-color:
initial; display: inline !important; float: none;">cs2cs
+proj=lonlat +ellps=WGS84 +to +proj=lonlat +ellps=GRS80 -d 8</span><br
style="box-sizing: inherit; color: rgb(29, 28, 29);
font-family: Slack-Lato, appleLogo, sans-serif; font-size:
15px; font-style: normal; font-variant-ligatures:
common-ligatures; font-variant-caps: normal; font-weight: 400;
letter-spacing: normal; orphans: 2; text-align: left;
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widows: 2; word-spacing: 0px; -webkit-text-stroke-width: 0px;
background-color: rgb(255, 255, 255);
text-decoration-thickness: initial; text-decoration-style:
initial; text-decoration-color: initial;">
<span style="color: rgb(29, 28, 29); font-family: Slack-Lato,
appleLogo, sans-serif; font-size: 15px; font-style: normal;
font-variant-ligatures: common-ligatures; font-variant-caps:
normal; font-weight: 400; letter-spacing: normal; orphans: 2;
text-align: left; text-indent: 0px; text-transform: none;
white-space: normal; widows: 2; word-spacing: 0px;
-webkit-text-stroke-width: 0px; background-color: rgb(255,
255, 255); text-decoration-thickness: initial;
text-decoration-style: initial; text-decoration-color:
initial; display: inline !important; float: none;">-120 40</span><br
style="box-sizing: inherit; color: rgb(29, 28, 29);
font-family: Slack-Lato, appleLogo, sans-serif; font-size:
15px; font-style: normal; font-variant-ligatures:
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text-indent: 0px; text-transform: none; white-space: normal;
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text-decoration-thickness: initial; text-decoration-style:
initial; text-decoration-color: initial;">
<span style="color: rgb(29, 28, 29); font-family: Slack-Lato,
appleLogo, sans-serif; font-size: 15px; font-style: normal;
font-variant-ligatures: common-ligatures; font-variant-caps:
normal; font-weight: 400; letter-spacing: normal; orphans: 2;
text-align: left; text-indent: 0px; text-transform: none;
white-space: normal; widows: 2; word-spacing: 0px;
-webkit-text-stroke-width: 0px; background-color: rgb(255,
255, 255); text-decoration-thickness: initial;
text-decoration-style: initial; text-decoration-color:
initial; display: inline !important; float: none;">-120.00000000
40.00000000 0.00000000</span></p>
<p>Do I need to do a transformation pipeline per the 8.2.1 docs
and use a Helmert transform? Any help much appreciated.</p>
<p>Best,</p>
<p>Joe</p>
<p><br>
<span style="color: rgb(29, 28, 29); font-size: 15px;
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text-decoration-style: initial; text-decoration-color:
initial; display: inline !important; float: none;"></span><span
style="color: rgb(29, 28, 29); font-family: Slack-Lato,
appleLogo, sans-serif; font-size: 15px; font-style: normal;
font-variant-ligatures: common-ligatures; font-variant-caps:
normal; font-weight: 400; letter-spacing: normal; orphans: 2;
text-align: left; text-indent: 0px; text-transform: none;
white-space: normal; widows: 2; word-spacing: 0px;
-webkit-text-stroke-width: 0px; background-color: rgb(255,
255, 255); text-decoration-thickness: initial;
text-decoration-style: initial; text-decoration-color:
initial; display: inline !important; float: none;"></span></p>
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