How To: Set a view's map units and projection


On-the-fly projection displays data in a different coordinate system than the data is actually stored in. It is possible to project vector data on-the-fly by setting a view's projection property. Raster data is not affected by this setting.

The projection for a view can be set only if all vector data in the view uses the Geographic Coordinate System (Decimal Degrees). All ArcView sample data is in this system.

If the view contains vector data that is already projected, it is not possible to set a view projection. Instead, set the view's map units to the native units of your data.


  • To set a view's projection:

    1. Select Properties from the View menu.
    2. Click Projection on the View Properties dialog.
    3. Choose the desired projection from the Projection Properties dialog and click OK.
    The map units are set to meters, but any map unit can be selected.  
  • To set a view's map units:

    1. Select Properties from the View menu.
    2. Set the Map Units to the desired units.
    The map units are the units used by the data in the view.