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+<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
+<html>
+<head>
+<meta http-equiv="Content-Type" content="text/html; charset=utf8" />
+<title>
+Orthographic Height - Geoid and Ellipsoid
+</title>
+<link rel="stylesheet" type="text/css" href="../../../css/main2.css" />
+</head>
+
+<body>
+<H1>Orthographic Height - Geoid and Ellipsoid</H1>
+<div class="centre"><img alt="" src="/handbook/survey/i/orthoheight.jpg" />
+</div>
+
+<p>How the Ellipsoid height (which is what GPS reports) relates to the geoid height (altitude above mean sea level). Though many GPS devices say they report height above sea level, they are probably lying.
+
+&lt;p&gt;
+From &lt;a href=&quot;https://support.virtual-surveyor.com/support/solutions/articles/1000261349-the-difference-between-ellipsoidal-geoid-and-orthometric-elevations-&quot;&gt;support.virtual-surveyor.com/support/solutions/articles/1000261349-the-difference-between-ellipsoidal-geoid-and-orthometric-elevations-&lt;/a&gt;</p>
+
+
+<p class="caption">Photo &copy; Philip S, 2023</p>
+
+
+<hr />
+</body>
+</html>
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