I am supplying a polygon with multiple features to be uploaded as a geofence layer in a Web AVM. The dataset is projected (MGA94). For some reason they can't work with metres and have requested the dataset in latitude and longitude. How can I convert or "unproject" my dataset? I have tried setting the coordinate system of the dataframe in ArcMap to a geographic coordinate system (GDA94) and exporting the data that way but the value of the coordinates doesn't change.

  • When you export your data you need to click the radio button for 'Same as dataframe' because it defaults to 'Same as input data' which results in an unchanged projection. You can use the Project tool in ArcGIS resources.arcgis.com/en/help/main/10.2/index.html#//… to convert your data into GDA94. MGA94 uses the GDA94 datum so no transformation need be supplied. – Michael Stimson Jun 21 '17 at 1:39
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    @MichaelMiles-Stimson, can you please put your comment as answer, over! – fatih_dur Jun 21 '17 at 4:42
  • Done @fatih_dur. – Michael Stimson Jun 21 '17 at 4:50

As you've set your ArcMap data frame to GDA94 and you've seen your data warp correctly you can right click export but, as you've found out, by default the output spatial reference is unchanged. To instruct ArcMap to export to the data frame coordinate system you must check the box: enter image description here

If you want to convert your data without a right click export use the project tool and specify the output projection as GDA94/Geographic (GCS_GDA_1994). MGA94 (zone) is based on the GDA94 datum so a transformation isn't required.


If you're talking about fields in the attribute table that aren't showing the right CRS try:

  1. Create new fields in the attribute table(latitude and longitude as Double data type)
  2. Right click on the new field's header and select Calculate Geometry
  3. Make sure the radio button for Use coordinate system of the data frame is selected (assuming the data frame is in a geographic coordinate system)

This should display the geographic coordinates in the attribute table for exporting.

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