A Quick Look at DEM's
Digital Elevation Model's (DEM's) a interesting little data sets. They have a variety of interesting uses including flashy images the general public can appreciate. Although the name is applied to many data types (including the DTED), we will use it exclusively to refer to the digital 7.5' quadrangle.
The state of Ohio provides 100% DEM coverage of the state. Start by finding the quadrangle you want on the quadrangle index map. When you have the name of the quadrangle, find the file name and location here. Copy and download the file to you local machine and unzip it.
These data are actually in an older format (which I like very much). It's actually all in ASCII. Try opening it in Notepad. Here's a description of what all of the fields mean.
I've downloaded and unzipped the datasets for two local quads, Hooven and Addyston and put them on geocopter. Download them to your local machine and open them in Global Mapper. 1