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Hi Carson,<div><br></div><div>indeed it does. As mentioned in my previous mail, i've solved the problem by simply exporting the lines into a new projection (in this case: british national grid). Although it is possible doing it this way, i really would apreciate if there would be a much smarter behaviour for this in qGIS in the future ;)</div><div><br></div><div>Thanks,</div><div>Freddy<br><br><div><br><b><span class="ecxApple-style-span" style="font-family:arial;font-weight:normal;font-size:small"><b>Frederick Löbig</b><br>Röderichstraße 59<br>60489 Frankfurt am Main<br>---<br>E:: <a href="mailto:Frederick.Loebig@grunsnid.de">Frederick.Loebig@grunsnid.de</a><br>P: +49 (0) 69 - 78 99 52 41<br>M: +49 (0) 174 - 70 89 296<br>---<br><b>Office:</b><br><b>euNetworks GmbH</b><br>Ludwig-Landmann-Straße 405<div>60486 Frankfurt am Main</div><div>P: +49 (0) 69 - 90 554 - 532<br>E: <a href="mailto:Frederick.Loebig@eunetworks.com">Frederick.Loebig@eunetworks.com</a><br>S: floebig<br><br>This email and any attachments may contain confidential and/or legally privileged information. If you are not the intended recipient, please delete the email without reading it and notify the sender.</div></span></b></div><div style="z-index:-1;top:0px;left:0px;width:100%;height:294px"></div><br><br><br><br>> Date: Fri, 4 Mar 2011 18:49:32 +0000<br>> Subject: Re: [Qgis-user] Incorrect Results in Buffer<br>> From: carson.farmer@gmail.com<br>> To: frederick.loebig@grunsnid.de<br>> CC: frederick.loebig@live.de; qgis-user@lists.osgeo.org<br>> <br>> Hi Frederick,<br>> <br>> > The situation: I have my project SRS set to EPSG:900913 (web mercator). As a<br>> > layer I have a line-layer also with EPSG:900913 as a projection. The<br>> > project-wide units are meters. I now want to add a 250m buffer around the<br>> > lines so i click vector->geoprocessing tools->Buffer(s), select my<br>> > line-layer, type in 250 for 250 meters, check dissolve buffer results ans<br>> > set a filename. Then the buffer is created, but unfortunately, when I export<br>> > the buffer as kml and check the buffer width in Google Earth it is around<br>> > 150-160 meters, so far off my 250meters. I also checked the distance with<br>> > the qGIS measurement-tool - same result.<br>> By 'same result' here, do you mean it measures 150-160 metres in QGIS as well?<br>> > The lines are located in London. I have tried to use simple WGS84 and the<br>> > british nationale grind, but none of them worked.<br>> What does this mean? No output was created, or they produced similarly<br>> 'wrong' results?<br>> > This has to do something with differente base-ellipsoids I think, but I did<br>> > not get to the bottom of the problem.<br>> > Could anybody please help me with this?<br>> Well one possible issue could be due to the fact that fTools (i.e. the<br>> vector menu), does not take into account the project CRS _or_ 'on the<br>> fly projection'. In fact, it only considers the CRS of the unput<br>> layer. This being the case, if the units for your input layer aren't<br>> in metres, then neither will your output. There are several reasons<br>> for why fTools does this, though it's possible that this will be<br>> changed in the future.<br>> <br>> Does that shed any light on the error?<br>> <br>> Carson<br>> <br>> -- <br>> Carson J. Q. Farmer<br>> ISSP Doctoral Fellow<br>> National Centre for Geocomputation<br>> National University of Ireland, Maynooth,<br>> http://www.carsonfarmer.com/<br></div> </body>
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