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I have a satellite image over the area of Forez, France.

I checked that the landmarks on the corner points coincide with the landmarks of Google Maps at the same coordinates, so the image is not misregistered itself.

I download OpenStreetMap (OSM) data (I tried from OSM site, including a mirror, and with QGIS but the problem persists).

The data is misregistered in a range of 100-300 meters in a non constant way, so I cannot correct it globally. This is the case when I download the image but if I browse, for instance, the mapbox.com map while overlaying it to the satellite image there, I can see it is correct in that case.

It looks that I am getting wrong data for this area when I download it. I checked the same procedure on several other cities and it works as expected.

I was thinking that maybe the points are expressed in another crs, but OSM data is supposed to use WG84 in every case.

Do you have any clues about what could be going on?

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Don't trust Google Maps or satellite imagery if it comes to an offset of a few hundred meters, especially in hilly areas.

Mapbox might use different satellite sources (like bing), which might be better aligned or was simply the basis for OSM digitizing.

To decide which is right and wich is wrong, take official digital datasources as a reference. For usage in OSM, these services are recommended:

http://wiki.openstreetmap.org/wiki/Potential_Datasources/France

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  • Hi, the image was in fact not orthorectified. It was the image I had that needed correction and not OSM data. I followed your advice and double-checked OSM data by comparing it to an official source.
    – user116773
    Jun 1, 2015 at 9:02

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