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I have some Points in Shapefile with BC Albers Coordinate Syetem and I need to Project them to Google Maps Lat and Long. I tried to do this by using 

WGS 84 / Pseudo Mercator EPSG: 3857

and 

WGS84 EPSG: 4326

But none of them returning correct result! I believe there is Coordinate for Google Maps in ArcGIS as "Web Mercator" to do this but I couldn't find it in QGis.

What Coordinate should I use for Getting correct points X and Y on google map?

I also used EPSG:900913 Google Mercator but when I tried to get X and Y coords through Geometry Tool/ Export add Geometry Columns I am getting numbers like :

enter image description here

Result using EPSG:3857:

enter image description here

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7
  • If you're looking for lat/longs, then 4326 is your destination coordinate system.
    – Mintx
    Commented Jan 30, 2015 at 20:37
  • Thanks Mintx 4326 looks more like lat and long but what I am getting are wrong coordinates!
    – Suffii
    Commented Jan 30, 2015 at 20:53
  • Could you give an example of a coordinate before and after converting?
    – Mintx
    Commented Jan 30, 2015 at 20:55
  • Like actual file?
    – Suffii
    Commented Jan 30, 2015 at 20:55
  • It looks like some of your source coordinates are swapped. If the area of interest isn't too large and should relatively near Vancouver, all x values should be >1 million. Thus point 1, 9, 13, etc need their values swapped.
    – mkennedy
    Commented Jan 30, 2015 at 21:01

1 Answer 1

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What you need to do is first display your CSV in the proper coordinate system (BC Albers) so QGIS can then re-project it to Google Maps Mercator (3857).

EPSG:3857 -- WGS84 Web Mercator (Auxiliary Sphere) is what you want.

So what you need to do is add your CSV to QGIS using 'Layer > Add Layer > Add Delimited Text Layer'.

Choose the default options in the first window:

enter image description here

The next window will ask you what coordinate system you want to use to display your X and Y values. You know it is in BC Albers, so choose that option in the dialogue box:

enter image description here

Now your points - still in BC Albers - will display in QGIS - but this is tricky because you will have a hard time displaying the various OpenLayers backgrounds with this data.

Here are the points on their own:

enter image description here

The last step is to actually re-project your data to Google Maps projection

Right-click the sample (CSV / delimited) layer in QGIS > Save As

Format: ESRI Shapefile
Save as: give your new SHP a name
CRS: Selected CRS > choose EPSG:3857 WGS84 / Psuedo Mercator**

Click OK to export and re-project your CSV to SHP in 3857

Now create a new map (to reset the coordinate system of the QGIS project)

Add your SHP you saved, and from the Web > OpenLayers menu add one of the basemaps:

enter image description here

That should do it!

Updates:

**The difference between EPSG:3857 and EPSG:3785 in QGIS is confusing, and I'm not exactly sure what the purpose of 3785 is... Most if not all web map systems are published using EPSG:3857 yet in QGIS the description for 3785 is "Popular Visualization CRS / Mercator" and the description for the CORRECT web mercator is "WGS 84 / Pseudo Mercator". I will take up this issue somewhere else!

Update #2: I see in this thread that 3785 is the deprecated version of the 'google maps' coordinate system... I hope QGIS can make note of this soon...

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4
  • Thanks MapBaker but I am not getting Correct value for X and Y at EPSG:3857!
    – Suffii
    Commented Jan 30, 2015 at 20:26
  • I uploaded an image showing the result of X and Y at EPSG:3857, can you please take a look at that?
    – Suffii
    Commented Jan 30, 2015 at 20:30
  • @Behseini updated my answer with the correct CRS/EPSG value and the steps to get your data working correctly...
    – Inactivated Account
    Commented Jan 30, 2015 at 21:44
  • @Behseini you are welcome!!! good luck!
    – Inactivated Account
    Commented Jan 30, 2015 at 22:38

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