Thank you to all who responded to my question, what is a DEM. Especially to Jason (Jason.Adam[jadam]@monopros.ca), Alex (Alex.Machinis[AMachinis]@empowergeo.com) for his sense of humor, and Patrick ([EMAIL PROTECTED]) for giving me what is was along with what the letters stood for. Basically I learned that a DEM is a Digital Elevation Model. It is a text file set up on a grid with spot elevations uniformly spaced over a known area. With it you can produce a topographic map, or a wire frame (also known as a grid) and subsequently a 3D rendering of the area. You start with satellite and/or surveyed elevation points, then a program like Vertical Mapper or the MapInfo Grid Thematic style will figure out (interpolate) the elevation values in between those points. You end up with a raster file where each pixel is given a value - it's elevation. Then you can color and sun-shade those pixels to show the elevation as a backdrop for your maps. Vertical Mapper and ERmapper allow you to look at this data from different angles too so that you can actually see the hills and valleys of your mapped area - 3D action! (I'm plagiarizing like mad - Patrick and Jason actually wrote this) Thanks, Sarah Myers Preventive Care Operations Blue Cross of California [EMAIL PROTECTED] ---------------------------------------------------------------------- To unsubscribe from this list, send e-mail to [EMAIL PROTECTED] and put "unsubscribe MAPINFO-L" in the message body, or contact [EMAIL PROTECTED]
