Trouble creating surface from DEM

[breyrw]

I have downloaded some dem files from the USGS site and I am trying to create a surface from that data. I can create a surface based on the dem, but it is extremely small. I don't think that it is using the correct coordinates for some reason. The dem is a rather large area, but in c3d it less than .1" across. Can anyone give some help as to how to get the surface to be the correct size? Thanks, RJ.

[brian.hailey933139]

Make sure you you assign the appropriate coordinate systems when you add the DEM.
http://i25.tinypic.com/2i9k1zl.png

[breyrw]

I assigned the coordinate system for the dem in that window but it does not change anything. When I reopen that window, without doing any other operation, it looses the coordinate system that I put in there and is blank again.

[brian.hailey933139]

Do you have a coordinate system assigned to the drawing under the drawing settings?

[jmeyer.186809]

You have to use Lat/Long 83. It will set the correct sub set for your local coordinate system but use the 83 lat/long code and it will work perfect.