Sounds to me like it has the incorrect datum set. E.g. it says it's NAD83 but in reality is NAD27.<br><br>
<div class="gmail_quote">On Tue, Dec 22, 2009 at 8:12 AM, NopMap <span dir="ltr"><<a href="mailto:ekkehart@gmx.de">ekkehart@gmx.de</a>></span> wrote:<br>
<blockquote style="BORDER-LEFT: #ccc 1px solid; MARGIN: 0px 0px 0px 0.8ex; PADDING-LEFT: 1ex" class="gmail_quote"><br><br>Hi!<br><br>I am building a map with several layers containing OSM geometry and<br>hillshading+contours. The rendering chain for the hillshading is<br>
<br>SRTM GeoTiff -> gdal_merge -> gdal_warp -> hillshading.exe -> mapnik<br><br>Now I have the problem that the hillshading and the geometry do not<br>quite match. It seems the hillshading is offset some constant distance<br>
to the north and west. I suspect as the offset looks like some 100m that<br>this is a result of the sample size of the SRTM data and the particular<br>hillshading algorithm.<br><br>Now I am looking for a way to correct this offset, so that optically the<br>
shading rests in the expected position relative to the geometry. But I don't<br>know how to do this. I have tried modifying the projections for gdal_warp<br>with some false northing, but the results always remains the same.<br>
<br>Any idea on how to move the hillshading 100m to the south?<br><br>thank you<br><br> Nop<br><font color="#888888"><br><br><br>--<br>View this message in context: <a href="http://n2.nabble.com/Which-tool-to-add-an-offset-tp4204322p4204322.html" target="_blank">http://n2.nabble.com/Which-tool-to-add-an-offset-tp4204322p4204322.html</a><br>
Sent from the GDAL - Dev mailing list archive at Nabble.com.<br>_______________________________________________<br>gdal-dev mailing list<br><a href="mailto:gdal-dev@lists.osgeo.org">gdal-dev@lists.osgeo.org</a><br><a href="http://lists.osgeo.org/mailman/listinfo/gdal-dev" target="_blank">http://lists.osgeo.org/mailman/listinfo/gdal-dev</a><br>
</font></blockquote></div><br><br clear="all"><br>-- <br>Craig Miller<br>Geospatial Software Architect<br>