Using Georeferencer to Reference Vector Data

This tutorial will demonstrate the basic workflow of referencing vector data using MAP Locations and the Georeferencer tool. See the Georeferencer for detailed information.

1.In Adobe Illustrator, open toronto.ai from \Tutorial Guide & Data\Tutorial Data.

This is a regular Adobe Illustrator document. It contains two Adobe Illustrator layers that do not have any georeferencing or attribute information. However, the data was known to be digitized in NAD 83/UTM Zone 17N coordinate system.

2.From the Tools toolbar, click and hold the MAP Location Tool button and choose MAP Page Location Tool. The cursor changes to a crosshair.

Three MAP Page Locations appear in the document. You need at least four MAP Page Locations to georeference a map.

3.Pan and zoom to the location pointed out in the graphic and click once. In the Add MAP Page Location dialog box, type Queens Park into the Name box.

addmappagelocation

A MAP Page Location is placed in the document at the X,Y page coordinates above. (Your coordinates may be slightly different depending on where you clicked. You can adjust the X and Y values accordingly.)

4.From the MAPublisher toolbar, click the Georeferencer button.

georeferencerbutton

More about Map Locations
MAP Locations do not belong to any layer within the document, rather, they act as annotations that are independent of other features. MAP Locations can be used to reference page locations (green pin) and world locations (blue pin) - default colours, custom colours can be chosen. These were created for you for the purpose of this exercise. To georeference, a minimum of four MAP Page Locations are required.

georeferencernew

The Georeferencer dialog box opens. Two MAP Page Locations have already been assigned world locations for the purpose of this exercise. You'll need to assign two more world locations to the other MAP Page Locations: one manually and one using the online map interface.

5.Click the Add reference location button.

lennox-lippincott

The Lennox/Lipponcott MAP Page Location is added to the list (MAPublisher automatically finds any available MAP Page Locations that don’t have an accompanying world location.)

6.Double-click the X|Longitude or Y|Latitude cell box.

7.In the Edit Location dialog box, enter the following values: Long: -79.409466 and Lat: 43.664095. Then click OK.

manualeditlocation

A world location has been manually assigned to the Lennox/Lippincott MAP Page Location.

lennoxworldlocationassigned

You'll assign the last MAP Page Location with world coordinates using the online map interface.

8.In the Georeferencer dialog box, click the Add world locations from button.

9.Ensure the Matching MAP Page Location drop-down has Queens Park (UNASSIGNED) selected. On the right side of the map, click the Zoom out [-] button until you can see two other placed world locations.

10. Type Queen's Park into the search box. (If no search result appears, zoom out again). Zoom into the north side of Queens Park and compare it to the features on the artboard.

queensparkunassigned

11. Click the map to assign a world location to the Queens Park MAP Page Location.

zoominqueenspark

12. Click Yes when asked to confirm. A placemark will appear on the MapQuest map to signal where you clicked.

world-location-added

13. Click OK to close the Add World Locations dialog box.

all-georeferencer-points-added

14. Click Georeference & Save.

The data was known to be digitized in NAD83 / UTM Zone 17N. It is the most appropriate coordinate system to use. Sometimes a coordinate system may not have the highest Rank, but may be the most appropriate to use. You'll also view some of the error introduced with georeferencing.

15. In the list, click the Show More Results button. Find and click NAD83 / UTM Zone 17N. At the bottom of the dialog box, click the Error Details button.

selectcoordinatesystem

errordetails

The table shows Error X, Error Y, and Combined Error. These errors come from how accurately the MAP Page Locations are assigned world locations. Lower error values means a higher georeferencing accuracy. Your errors may vary depending on how accurate you placed your MAP Locations.

16. Click OK to close the Error dialog box.

17. In the Select Coordinate System dialog box, click OK.

18. In the Create MAP View dialog box, change the MAP View name to Toronto. Click the two check boxes beside the Streets and Postal Code Area layers. Then click OK.

createmapview

19. Assign the appropriate MAP Layer type: Line for Streets; and Area for Postal Code Areas.

assignarealine

The MAP Views panel updates and lists the Toronto MAP View and two layers.

georeferencerdone

20.From the MAPublisher toolbar, click the MAP Locations panel button.

maplocationspanel

This panel allows you to see all of the MAP Page and MAP World Locations. The panel lists the four MAP Page Locations and the four newly added MAP World Locations. Georeferencing with more than four page locations may yield better referencing results.

21. The document is now georeferenced.

22. Close the document without saving.

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Last updated: 12/11/2020