Hi,<br><br>I have a problem in QGIS 1.4.0 when I reproject a gpx file
into Belgian lambert 72 coordinate system : the waypoints are not
correctly placed on the map (see the image <a href="http://www.fsagx.ac.be/gf/outilslogiciels/Garbel/proj4.jpg" target="_blank">http://www.fsagx.ac.be/gf/outilslogiciels/Garbel/proj4.jpg</a>, correct positions are in red). In QGIS, the towgs84 parameters are '+towgs84=106.869,-52.2978,103.724,-0.33657,0.456955,-1.84218,1' for this coordinate system. According to a discussion on the proj.4 mailing list (<a href="http://lists.maptools.org/pipermail/proj/2010-January/005016.html">http://lists.maptools.org/pipermail/proj/2010-January/005016.html</a>), the correct parameters seems to be '+towgs84=-99.059,53.322,-112.486,0.419,-0.830,1.885,-1' (accurate to a meter) or '+towgs84=-106.8686,52.2978,-103.7329,-0.3366,0.457,-1.8422,-1.2747' (accurate to 20 cm).<br>
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<br>Best regards,<br><font color="#888888">Thibaut.</font></div>