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I have downloaded a kml file from Google containing location of shops. The coordinates in that file are in lat/long. I have other shp files containing roads and territories.

I am trying to have all those files in the same projection and since I need to work with buffers and distances, I figured NAD27 (EPSG: 26718) or WGS84 (EPSG:4326) were good choices (units in meters).

However, using QGis, I have tried to reproject the kml file with no success. Even though I can see that they have the same CSR in the metadatas, the kml file do not overlap with the other two shp files. For example, with NAD27 Zone 18 N set as the CSR, the kml file coordinates range from xMin,yMin 362234.57,45.4667 : xMax,yMax 362234.77,45.5717 while the shp file range from xMin,yMin 3271320.50,5039271.30 : xMax,yMax 305262.50,5064239.70.

Sooo would anyone give me a much needed helping hand?

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WGS84 EPSG:4326 does not have metres as units, but degrees. KML files are always in degrees, so you have to set CRS to that, then reproject the layer to someting else with Save As .... Maybe you have used Set CRS for Layer, which is wrong in most cases.

The extents you provide are a bit strange. For the kml, yMin and yMAx are very small, even if the point is a 1000-separator. For the second, xMin is 10 times than xMax.

With the extent from your comment below, it looks far better:

enter image description here

So which one is correct now?

  • :Indeed I am working on a small city in Canada. And you are right, the kml range is xMin,yMin 589470.47,5041677.69 : xMax,yMax 605209.98,5053473.06 while the shp one is xMin,yMin 271320.50,5039271.30 : xMax,yMax 305262.50,5064239.70. – jeake Mar 26 '14 at 17:04
  • @ Andre: Here are the steps I used: I opened the kml file on qgis, I saved the layer as a shp file with the new CSR (NAD27). I thought that was the way... isn't it? How come two files with the same CSR are not overlapping? Thanks! – jeake Mar 26 '14 at 17:07
  • One of them is wrong, just look at my exchanged image. – AndreJ Mar 26 '14 at 18:18
  • The Kml one is the right one. It's weird, I thought the shp one was wrong... So I guess I have to reproject the shp file... – jeake Mar 27 '14 at 16:31
  • No, not reproject, but find out which CRS was really ment for it, then assign it to the layer with Set CRS for layer. In most cases, shapefiles come with a .prj file that contains the CRS information, and QGIS should be able to understand that. – AndreJ Mar 27 '14 at 19:42

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