USAPhotoMaps...
...is a freeware/shareware application that you can use to download, view, and save topo maps and aerial photos from Microsoft's TerraServer site. The accuracy of it all will astound you. You don't need a GPS to use the program, but if you have one, you can plot routes and waypoints onto your downloaded aerial photo map and send them to your GPS receiver. You can import waypoints and tracks from your GPS to the program and then download aerial photos of the terrain you have crossed.
What's TerraServer...
If you've never used TerraServer before, it's an online database of USGS (US Geological Survey) topo maps and aerial photos of the USA. The maps/photos are broken up into very small tiles and indexed according to their coordinates (longitude and lattitude). The maps/photos are then accessed free of charge using the website's highly advanced search function. You can search the database using either an address, placename, or by entering the actual coordinates of the area you'd like to view.
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A screenshot showing some of the the many features of USAPhotoMaps. Display of elevation contour lines as shown above requires separate downloads of USGS digital elevation data which is also available free of charge on the web. |
Click to visit TerraServer
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The site will display a maximum of 12 tiles at one time. There's a link on the page you may use to toggle between the topo maps and aerial photos. You can pan the map or photo by clicking N-S-E-W arrows to download a new set of tiles. You may also click the map at the spot you're interested in to zoom and re-center the map, but you will still only be able to see a maximum of 12 tiles at any given time. Using TerraServer as a map, is a difficult task with this relatively small field of view. Panning the map is a slow process if you're using a dial-up internet connection. You must download each tile of the new map regardless of whether or not you've previously downloaded them.
Enter USAPhotoMaps...
This is where USAPhotomaps comes in. Sort of like your own personal "back door" into TerraServer's massive database. You can create a large zoomable, scrollable collection of tiles making it much easier to get the "lay of the land". The tile collections are saved to a folder on your hard drive so you can view your downloaded maps at any time without being connected to the internet.
With USAPhotoMaps you can superimpose text, waypoints, routes, and tracks directly onto the aerial photos. You can toggle between your downloaded aerial photos and topo maps with the press of a key. With additional 3rd party downloads of digital elevation data, USAPhotoMaps can even display elevation contour lines on aerial photos.
Getting Started...
There are websites that go into great detail about using USAPhotomaps, so I wont repeat what has already been written. Here's a quick run-down of the basic functions of the program followed by some links to more information:
- Download and install the program
- The first time you open USAPhotomaps, you will be prompted to create a "new map". You must enter the coordinates of the location you want to see. You are creating a waypoint at the coordinates you entered and you will be prompted to give the waypoint a name. The waypoint will snap to the center of the screen so that USAPhotoMaps can begin downloading photos of the area.
- Choose whether you want to download topo maps or aerial photos of the area by pressing "T" (topo) or "P" (photo) on your keyboard.
- Select your zoom level by pressing "Page Up" (zoom out) and "Page Down" (zoom in). I recommend max zoom (1 meter photo or 4 meter topo) for first downloads.
- Press your "F" key for "Fill Screen", and the tiles will begin downloading from the lower left corner of the screen.
Caution: Filling a screen that is zoomed all the way out may take hours with a dial-up internet connection.
- Create new waypoints by clicking precisely where you want the waypoint to be. You will again be prompted to give the new waypoint a name.
- Right click the map for a list of your waypoints. Highlight a waypoint and click "Go To" to snap the highlighted waypoint to the center of the screen.
- Use your arrow keys to scroll the downloaded maps left and right or up and down.
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