Mapping Hacks

Mapping Local Areas of Interest with Quantum GIS #64

Chapter 6, Mapping on Your Desktop

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HACK

Now we have the georeferenced DRG saved as a JPEG image.

Next we will get the DOQ for the same area. Click on the “Back to Terraser-

ver” link below the DRG image to go back to the map display. To down-

load the DOQ:

1. Find the “Other Imagery” section in the left panel. For Burro Canyon

there is a link to an aerial photo taken September 21, 1992.

2. Click on the link to display the image.

3. Download and save both the image and the world file using the same

process used for the DRG (Steps 4–6). Name the image burro_canyon_

doq.jpg and the world file burro_canyon_doq.jgw.

Displaying the Data

Now we can look at the data layers we have downloaded. The advantage to

using a GIS is that we can view the layers along with other data we might

Figure 6-2. Search results from the GNIS

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Chapter 6, Mapping on Your Desktop

#64 Mapping Local Areas of Interest with Quantum GIS

HACK

have. QGIS allows you to overlay multiple layers, including data imported

from a GPS using the QGIS GPS-importer plug-in.

To display the Burro Canyon data, start QGIS and follow these steps:

1. Click on the “Add a Raster Layer” toolbar button or choose “Add a Ras-

ter Layer” from the View menu.

2. Change the “File type” to “All other files” ...