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- The map takes on the projection of the first layer added. If a JPG is added first, then the map projection would be undefined (as the projection for a JPG is undefined). To define the map's coordinate system, in the Contents pane on the right, right-click the PlayMapping map and navigate to Properties > Coordinate System > Geographic Coordinate Systems > North America > US and Territories > NAD 1927. We use a geographic coordinate system because the data given is in degrees. We know to use NAD 1927 because the degrees data acquired from BEG course instructors is in NAD 1927.
- RightIn the Catalog pane, right-click the HST.jpg raster and select Add To Current Map.
- An alternative method of adding data to a map is to click and hold the item and drag and drop it into the map view.
Georeferencing
For more practice with Georeferencing, check out our short course: Mapping Imagery
- In the Contents pane, right-
- Under the Map ribbon, click Add Data. Navigate to your folder. Click HST.jpg then click OK.
- If you can see HST.jpg, skip to step 3. If you can not see the HST.jpg, under Contents, right click HST.jpg then click Zoom to Layer.
- Under contents, click HST.jpg. On the menu ribbon, click Imagery > Georeference.
- Click Add Control Points.
- Click the top left corner of the HST.
- Right click and select Input X and Y ...
- Type X : -104.5, Y : 33 and click OK. The x value is the West coordinate in this case and it is negative because we are in the Western Hemisphere. The y value is North in this case.
- Right click HST and click zoom to layer.
- Repeat steps 5-8 for the bottom right corner of HST but type X : -103.5, Y : 32.
- Repeat steps 5-8 for the new bottom left corner of HST but type X : -104.5, Y : 32.
- If HST looks perfectly square, skip this step. If not, repeat steps 5-8 for the top right corner and type X : -103.5, Y : 33.
- Now, from the Georeferencing menu, click save. Then click Close Georeference.
- Under Contents, slowly double click HST.tiff and rename it HST.
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