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I need to use a waste dump .dxf on a map but unfortunately I'm not able to match the projection with the others I have. I'm working with Google hybrid using CRS: EPSG:32632 WGS84 / UTM zone 32N and this is the area I'm working on:

enter image description here

And I'm trying to use this .dxf which is projected far away from the ara of interest:

enter image description here

I think there's something wrong with the projection I'm using, but even changing the CRS of the layer doesn't change the result.

Here's the dxf: https://infinit.io/_/3cygVkS

  • Did you reproject the satellite picture to EPSG:32632? – underdark Jan 10 '17 at 19:35
  • Yes I did. But the .dxf is still projected near Africa instead in Italy as expected :/ – Mirko Jan 11 '17 at 10:18
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After some trial and error, you may find this custom CRS to fit rather good:

+proj=tmerc +lat_0=0 +lon_0=9 +x_0=-100022 +y_0=-4901952 +datum=WGS84 +units=m +no_defs

This makes me think the projection is Monte Mario Zone 1, with the leading digits cut off:

+proj=tmerc +lat_0=0 +lon_0=9 +k=0.9996 +x_0=-100000 +y_0=-4900000 +ellps=intl +towgs84=-104.1,-49.1,-9.9,0.971,-2.917,0.714,-11.68 +units=m +no_defs
  • Thank you @AndreJ! the custom CRS you passed me works perfect! – Mirko Jan 12 '17 at 10:51
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If you are sure that all your projection settings are right and it still does not work, you might want to try vector georeferencing aka "rubber sheeting". See How to georeference a vector layer with control points? and/or try the VectorBender plugin.

3

The middle of your DXF are approximately x: 24,500 y: 20,500. Your Google Picture is located at approximately EPSG: 32632 X: (32) 625,000 Y: 4,920,500. It looks like you have to move your DXF by x: 600,000 y: 4900.000.

I have tested again: Create a CRS for the DXF with the following values:

+proj=tmerc +lat_0=0 +lon_0=9 +k=0.9996 +x_0=-100000 +y_0=-4900000 +ellps=intl +towgs84=-104.1,-49.1,-9.9,0.971,-2.917,0.714,-11.68 +units=m +no_defs
  • You can georeference data in QGIS/ogr2ogr but it is not too straightforward: gisforthought.com/… – HeikkiVesanto Jan 11 '17 at 14:28
  • @Mike What's the best way to move the DXF to the right position? – Mirko Jan 11 '17 at 16:59
  • V1) use a extern tool for DXF(Unknown to me) V2) Convert the DXF to Shape (PlugIn Another DXF Shape Converter) Move the Shape(s) with QGIS (PlugIn Affine Transformations) – Mike Jan 11 '17 at 19:14

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