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<p>This has me puzzled. So I may have screwed up a very large job
with incorrect acres and I was doing what I thought I needed to be
doing. I'm probably doing this wrong - but if I'm doing this wrong
there's a large chance more people are doing the same. <br>
</p>
<p>This is all in QGIS 3.0.1<br>
</p>
<p>I have a forester who is working on a tract of land. There was a
very hurried cruise they needed to do. <br>
</p>
<p>Data is in WGS84 and set to EPSG:2240 in QGIS. <br>
</p>
<p>Change the ellipsoid to None under project properties: <br>
</p>
<ul>
<li>using the identify button are 237 acres. <br>
</li>
<li>I get roughly 194 acres with the measure tool<br>
</li>
</ul>
<p>Changing the ellipsoid to GRS1980 (which QGIS Defaults to): <br>
</p>
<ul>
<li>I get 196 acres with the identify tool. <br>
</li>
<li> I use the measure tool I get 194 acres</li>
</ul>
<p>I am assuming the 194/196 measurements are the exact same and due
to human error on my part. PostGIS gives me 196 acres. <br>
</p>
<p>I guess (as I type this out) my correct course of action should
be to leave the ellipsoid in GRS1980 and do my work - BUT - I
thought I could drop back to none/planimetric if I set the
projection to EPSG:2240 in QGIS.</p>
<p>Can anyone clue me in - I'm preparing for much yelling from the
client in about 15 minutes as I was off about 40 acres which was a
costly mistake. I'm not confident currently in my area
measurements using QGIS and I need to get confident. <br>
</p>
<p>Randy<br>
</p>
<p><br>
</p>
<p><br>
</p>
<p><br>
</p>
<p><br>
</p>
<pre class="moz-signature" cols="72">--
Randal Hale
<a class="moz-txt-link-abbreviated" href="mailto:rjhale@northrivergeographic.com">rjhale@northrivergeographic.com</a>
<a class="moz-txt-link-freetext" href="https://www.northrivergeographic.com">https://www.northrivergeographic.com</a>
(423)653-3611
</pre>
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