<html><head><meta http-equiv="content-type" content="text/html; charset=utf-8"></head><body dir="auto">David,<div><br></div><div>Please write your question here:</div><div><div style="display: block;" class=""><div style="-webkit-user-select: all; -webkit-user-drag: element; display: inline-block;" class="apple-rich-link" draggable="true" role="link" data-url="https://qgis.org/resources/support/#communication-channels"><a style="border-radius:10px;font-family:-apple-system, Helvetica, Arial, sans-serif;display:block;-webkit-user-select:none;width:300px;user-select:none;-webkit-user-modify:read-only;user-modify:read-only;overflow:hidden;text-decoration:none;" class="lp-rich-link" rel="nofollow" href="https://qgis.org/resources/support/#communication-channels" dir="ltr" role="button" draggable="false" width="300"><table style="table-layout:fixed;border-collapse:collapse;width:300px;background-color:#04324F;font-family:-apple-system, Helvetica, Arial, sans-serif;" class="lp-rich-link-emailBaseTable" cellpadding="0" cellspacing="0" border="0" width="300"><tbody><tr><td vertical-align="center" align="center"><img style="width:300px;filter:brightness(0.97);height:191px;" width="300" height="191" draggable="false" class="lp-rich-link-mediaImage" alt="QGIScover.png" src="cid:97C1D628-4D39-4255-843F-ADD68806F2F2"></td></tr><tr><td vertical-align="center"><table bgcolor="#04324F" cellpadding="0" cellspacing="0" width="300" style="table-layout:fixed;font-family:-apple-system, Helvetica, Arial, sans-serif;background-color:rgba(4, 50, 79, 1);-apple-color-filter:initial;" class="lp-rich-link-captionBar"><tbody><tr><td style="padding:8px 0px 8px 0px;" class="lp-rich-link-captionBar-textStackItem"><div style="max-width:100%;margin:0px 16px 0px 16px;overflow:hidden;" class="lp-rich-link-captionBar-textStack"><div style="word-wrap:break-word;font-weight:500;font-size:12px;overflow:hidden;text-overflow:ellipsis;text-align:left;" class="lp-rich-link-captionBar-textStack-topCaption-leading"><a rel="nofollow" href="https://qgis.org/resources/support/#communication-channels" style="text-decoration: none" draggable="false"><font color="#FFFFFF" style="color: rgba(255, 255, 255, 1);">Contact and Support · QGIS Web Site</font></a></div><div style="word-wrap:break-word;font-weight:400;font-size:11px;overflow:hidden;text-overflow:ellipsis;text-align:left;" class="lp-rich-link-captionBar-textStack-bottomCaption-leading"><a rel="nofollow" href="https://qgis.org/resources/support/#communication-channels" style="text-decoration: none" draggable="false"><font color="#FFFFFF" style="color: rgba(235, 235, 245, 0.6);">qgis.org</font></a></div></div></td></tr></tbody></table></td></tr></tbody></table></a></div></div><br></div><div>QGIS-PSC is not the proper one 🙂</div><div><br></div><div><div dir="ltr"><div dir="ltr"><span style="background-color: rgba(255, 255, 255, 0);">Greatings,</span></div><div dir="ltr"><span style="background-color: rgba(255, 255, 255, 0);">Michał Żugajewicz</span></div><div dir="ltr"><span style="background-color: rgba(255, 255, 255, 0);"><br></span></div></div><div dir="ltr"><br><blockquote type="cite">Wiadomość napisana przez David Brownrigg via QGIS-PSC <qgis-psc@lists.osgeo.org> w dniu 19 lip 2025, o godz. 14:30:<br><br></blockquote></div><blockquote type="cite"><div dir="ltr">
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Have a dsm made by WebODM from a drone image set with inaccurate gps.</div>
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Contours made have a +45cm error.</div>
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In Raster->extract->contour I tried setting 'Set offset from zero' to -0.45</div>
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BUT resulting contours have the same numerical values as before.</div>
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What should I be doing (e,g for a contour labelled 10.50 to be labelled 10.05 in my case)?</div>
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