Approach_Medium
Trainz Addict
Hi;
When you are making selections in the USGS seamless server, make sure that you have "National Atlas Railroads" ticked. This will show rail lines once you are zoomed in far enough to get that detail on the map.
Before you make your selection, look at your GE maps, and make note of highways, rivers, etc that should be in your DEM. You can then locate the general area on the Seamless map.
If you are creating a large route, you will need to splice together a number of DEMs, each downloaded from USGS seamless server separately.
Transdem handles the splicing very neatly. Just open the first DEM, then for subsequent DEMs, select "Add Dem" instead of open.
This may be your whole problem, if your DEMs are not large enough to cover the area of your Raster map.
It is best to download smaller DEM sections from the Seamless Server, then merge them in Transdem, rather than select a much larger DEM to download.
For me, the problem is mainly memory. If I try to open too large a DEM (or merge too many smaller sections), I get a memory error. This is probably because I am running a 32 bit OS with only 3Gigs.
Also, if you create DEMs that only cover the area you want, your files will be smaller, and open, or convert faster in Transdem.
I hope this helps. One thing that is in your favor is the excellent tutorial in Transdem.
FW
When you are making selections in the USGS seamless server, make sure that you have "National Atlas Railroads" ticked. This will show rail lines once you are zoomed in far enough to get that detail on the map.
Before you make your selection, look at your GE maps, and make note of highways, rivers, etc that should be in your DEM. You can then locate the general area on the Seamless map.
If you are creating a large route, you will need to splice together a number of DEMs, each downloaded from USGS seamless server separately.
Transdem handles the splicing very neatly. Just open the first DEM, then for subsequent DEMs, select "Add Dem" instead of open.
This may be your whole problem, if your DEMs are not large enough to cover the area of your Raster map.
It is best to download smaller DEM sections from the Seamless Server, then merge them in Transdem, rather than select a much larger DEM to download.
For me, the problem is mainly memory. If I try to open too large a DEM (or merge too many smaller sections), I get a memory error. This is probably because I am running a 32 bit OS with only 3Gigs.
Also, if you create DEMs that only cover the area you want, your files will be smaller, and open, or convert faster in Transdem.
I hope this helps. One thing that is in your favor is the excellent tutorial in Transdem.
FW