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Old September 19th, 2012, 01:45 PM

kgambit kgambit is offline
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Default Re: Free TOPOGRAPHIC PROGRAMS -map designing powertool

Great stuff Pyros!

Here's a few updates:

The MICRODEM link Mark Shepard's post appears to be broken Here are the links to the MICRODEM home page and download pages:

http://www.usna.edu/Users/oceano/pgu...m/microdem.htm
http://www.usna.edu/Users/oceano/pgu...crodemdown.htm

Sources of free digital data for use with MICRODEM are listed in the help file for MICRODEM, but SRTM data is about the best available for elevations.

There are three sets of SRTM data: SRTM1, SRTM3 and SRTM30
SRTM1: United States, resolution ~30 m, 1 arc-sec
SRTM3: Global, resolution ~90 m, 3 arc-sec
SRTM30: Global, resolution ~900 m, 30 arc-sec

More information on the SRTM data set can be found here:

http://dds.cr.usgs.gov/srtm/version2.../SRTM_Topo.pdf

You can go to the following site and interactively find the appropriate SRTM file without an intermediate step to google to find lat/lon

http://earthexplorer.usgs.gov/

To preview the SRTM data, go to Data sets, Digital Elevation, then click SRTM or SRTM void filled

SRTM data file names refer to the latitude and longitude of the lower left corner of the tile - e.g. N37W105 has its lower left corner at 37 degrees north latitude and 105 degrees west longitude

one degree longitude = 111 km * cos(lat)
one degree latitude = 111 km
So the SRTM maps cover a LOT or territory

You can go to this site and click on the colored region to pull up a complete list of downloadable SRTM data files

http://www.webgis.com/srtm3.html

Files are anywhere from 300kb to 1.5 megs ZIPPED

PS: In addition to Google Earth, here are some handy online sites:

http://www.openstreetmap.org/
http://www.maps-for-free.com/
http://mapper.acme.com/
http://www.bing.com/maps/

http://www.lib.utexas.edu/maps/map_c...ion_guide.html
(Huge collection of downloadable maps)

Soviet-military-topographic-map (!) FREE downloads - GREAT site
http://maps.vlasenko.net/soviet-mili...pographic-map/
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