Hi there
Im trying to find away of making a custom google Terrain maps of mongolia? There doesn't seem to be any on the internet.
I have a garmin 62s and using Basecamp on a Mac
Is there any Gurus out there that can help?
I'm not familiar with Google Terrain Maps.
To generate a standard Garmin vector topo map, you might try here. (http://www.gpsfiledepot.com/tutorials/how-to-create-garmin-topo-maps/) But you'll probably need SRTM data, and I don't think the tutorial covers that. OpenStreetMap's compiler, mkgmap, can be used to make topo maps using SRTM data. SRTM data is extracted using this tool (http://katze.tfiu.de/projects/phyghtmap/). You can find out about the mkgmap compiler here. (http://wiki.openstreetmap.org/wiki/Mkgmap)
Globalmapper also will open SRTM data. I have been using it recently myself where I can't find LIDAR coverage. This is a long thread that gets complicated, but it may give you some ideas. However I have been converting DEM into polygons in order to make vector maps. If you want to use the Garmin "custom map" (raster) format, that will be much easier. http://forums.gpsfiledepot.com/index.php/topic,2579.0.html
Thought Gobal Mapper might be a little rich for the OP's blood, but if he's willing to spend $399 that's the easiest way to get contours and something to compile with cgpsmapper. I wonder where you'd find hydrography for Mongolia?
Google Maps has a terrain layer for Mongolia, what are you looking to do?
In that case, you might have a look at GoogleTrail or maybe OKMaps. These programs can make Garmin .kmz custom maps.