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I have georef some topocards with QGIS and the Google Hybrid Layer. So, this cards are connected with the Google Mercator System.

Now I have some waypoints taken with Garmin GPSmap62 (in WGS84).

When I try to load both datasets in QGIS, I get a mismatch of around 2000 km (don't know, the topocards are in bulgaria and the waypoints somewhere in the southern atlantic).

I tried to convert the topos to WGS84 and/or the waypoints to Google Mercator. Either qgis crashed down or nothing happens.

I'm working with Win7, and QGIS 1.7.4

\edit: First the Topocard. And I try to load up the gpx File, but I'm not sure how gg. Ah okay, it isn't allowed me to upload pictures, cause I'm a new user. sry

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  • My first guess was that the latitude /longitude were switched but that would result in points in ~Saudi Arabia. Commented Apr 14, 2012 at 17:17
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    Can you post sample data? Commented Apr 14, 2012 at 17:17
  • What should I try to upload?
    – Malte
    Commented Apr 15, 2012 at 5:27
  • If you upload the tiff and gpx file to some web space, you can link it here. It is not possible to upload spatial data to stackexchange.
    – underdark
    Commented Apr 15, 2012 at 11:23
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    @Malte, the TIFF has no georeference info.
    – dakcarto
    Commented May 15, 2012 at 13:18

2 Answers 2

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Enable on-the-fly reprojection in project settings. Make sure the Garmin waypoint layer is set to WGS84 in layer properties and the topocard layer is set to Web Mercator ("Google Mercator").

If you still have the OpenLayers layer loaded, you might experience problems if you try to set the project CRS to anything else but Web Mercator.

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  • Okay, at the moment I try to load the topocard (it's a tif file) and set it to Google Mercator my qgis is crashing down.
    – Malte
    Commented Apr 15, 2012 at 5:26
  • And when I load first the tif files (Google Mercator) and then the waypoints everything is fine till I hit the "On-the-Fly" Button. After that my qgis crashed down too.
    – Malte
    Commented Apr 15, 2012 at 5:41
  • Ah, at this point. Is it possible to save the georef tif files as an normal shape?
    – Malte
    Commented Apr 15, 2012 at 5:42
  • I would have to test with your files. These operations shouldn't cause crashes. The files might be corrupted or it could be a problem with your system.
    – underdark
    Commented Apr 15, 2012 at 11:24
  • See my comment up there
    – Malte
    Commented Apr 15, 2012 at 17:04
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If underdark's suggestion of enabling on-the-fly reprojection didn't work for you, try to verify both sources are indeed in the CRS and/or projection you think they are. From your post, I think I understand you have manually georeferenced the topocards. Cross-reference any know point on your georef'd maps with a trusted source (or the cards) to ensure you have georef'd them correctly.

To verify your GPS coords, and possibly reveal what format they are in, try loading them into gpsbabel (where you can convert the coords as well). You may also be able to open the GPS coords as a file in a text editor and read any meta info in them.

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  • I don't know why, but I can't load the gdb files in gpsbabel. But thank u, I'll try it later again...
    – Malte
    Commented Apr 15, 2012 at 6:40

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