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I have downloaded the OSM from OpenStreeMap that came with all nodes from the map and their respective coordinates. Now I have to plot a node (latitude and longitude) on Google Maps, but all coordinates end up in different places than they should.

To illustrate I'll show the node -12.92122,-38.34991 (lat,long) on OpenStreetMap and Google Maps, as you can see on screenshots:

OpenStreetMap http://i.stack.imgur.com/9Ac7R.png

Google Maps http://i.stack.imgur.com/Szyot.png

My question is how can I adjust these values.. so I can plot the node on google maps at the same place of openStreetMap. Google Earth uses WGS-84 coordinates, expressed in decimal degrees, and OSM uses WSG-84 as well.

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    Have you tried to overlay the two datasets to see if they are coincident? You may be seeing that the points are the same location but that the geometry you are wanting to be matched against actually have a different location in space.
    – D.E.Wright
    Oct 24, 2012 at 17:25
  • @D.E.Wright thanks for your reply.. I have verified different nodes and all of them have a different position on map (few meters of distance). It impacts on route because some points goes too near from another street then the google maps is considering the second street instead of the correct one, resulting in some big routes to places that are actually near. So that is why I don't believe that it is a problem with geometry location. Oct 24, 2012 at 17:52
  • Did you ever find an answer to this? I am also looking!
    – user70171
    Mar 29, 2016 at 14:23
  • Hey @user70171 the accepted answer from Moe is right, they are different datasets and there is no projection that will convert one into the other. Mar 31, 2016 at 7:48

1 Answer 1

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It is not possible to adjust for this because these are two completely different datasets. There is no projection or anything that will convert one into the other. OpenStreetMap data is (mostly) acquired by volunteers with GPS devices (sometime very precise) or people tracing aerial imagery (sometime very imprecise). Both types of data acquisition can have few meters error at least.

By the way: I wouldn't trust Google data to be of much better accuracy either.

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  • Humm Thanks @Moe, actually I am not trusting on google, it is just a requirement to plot the data on google maps.. but unfortunately this data came from OpenStreetMap and as you said it is not possible to convert one in the other.. I will consider to use the openstreetmap layer too instead of google maps.. thank you! Oct 25, 2012 at 13:15
  • @Moe, How do those GPS devices decide what geographic coordinate system to use? Sep 6, 2017 at 13:43
  • @TedTaylorofLife GPS device could has A CRS and the other GPS device could has B CRS, both CRS will represent point in some coordinates system. So point if it's accurate will be converted into the other CRS without disposition, the problem is that point accuracy is not ideal. GPS has information about CRS it uses, and if not it could be guessed sometimes by numbers or by additional inormation contained in GPS device dataset.
    – Rantiev
    Jan 23, 2019 at 11:03

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