Directions to get Digital Elevation Models into ArcView

For DEM's, you will get a zipped "*.tar.gz" file. You will need to create a new directory for the DEM and unzip it into that directory (there are a lot of files involved). To unzip, just double-click on the file name and follow the directions. Be sure you put the files into the directory that you just created for that purpose.

Next, you will need to run the program SDTSEDEM.exe, which can be found here. To do this:

1. Download the SDTSEDEM file into your new directory and double-click on it using Explore.
2. This should bring up a DOS window. Tell it what the first four characters of the base SDTS file name is (this will be the first four characters in the name of most of the files that you just extracted. You can see what it is using Explore.
3. Enter an output file name -- whatever you want
4. Enter the two characters in position 7 and 8 of the CELL file (again, use Explore to check -- this is always L0) (Note: zero not O)
5. Press enter and it should run -- there should now be a new file in the directory called *.dem

Now you have to get this into ArcView:

1. Load ArcView, add extensions 3D Analyst, Spatial Analyst.
2. Get into a new View.
3. Under File, choose Import Data Source, type=USGS DEM, then navigate to find your *.dem
4. ArcView will now create a grid -- this is a new file -- you have to tell it where you want it. Advice: put it into the same directory, or if you are creating a lot of these, create a new directory called MYDEMS (or whatever). You can also specify a file name such as Alpine South ...
5. Next, say yes to "Add grid to view?" and the grid should appear.
6. Turn it on in your view and you should see a color coded elevation model.
7. Now you can use the Surface menu to create contours, slope, aspect and hillshade models. The grid has to be "active" before these functions are available. (Note: the elevations are in meters, so keep this in mind when choosing a contour interval.)

Stop Here for Dem Lab #1

To make a 3D model:

1. In the Window menu, choose your project, click on 3D Scene, click on New
2. Press the Add Theme button, choose Data Source Type to be Grid, and find your grid. It will appear as a flat plane with the elevation colors.
3. Now, choose Theme/3D properties, click on the Surface radio button and the Show Shading for features button. Press Apply, then close the box.
4. Now you should see a 3D model. The left mouse button spins the model, the right button allows you to zoom in and out, both pressed together allow you to pan the model.
5. I personally do not like the colors -- to make it a gray color, double-click on the menu item of your grid -- you should see a legend editor box appear.
6. Click the Classify button, change the Number of Classes from 9 to 1, click OK.
7. Double-click on the red Symbol box and change the color to gray in the Color Palette box that appears.
8. Press Apply and close the Legend Editor Box.

To drape other data on top:

1. Add a shape file (an image file such as a DRG can also be draped).
2. Make the shape file active.
3. Choose Theme/3D properties.
4. Click on the Surface radio button, change offset heights to 10.
5. Press Apply and close the box.