More free maps from NASA ..

GSV Three Minds in a Can said:

For those of you bored with Worldwind (or without a fast enough
connection to download it all), you can download the individual (degree
square) SRTM (Shuttle Radar Topography Mission) tiles from:
ftp://e0dps01u.ecs.nasa.gov/srtm/Eurasia

The name of the file tells you where the bottom left corner is eg N52W02
covers 52N to 53N, 2W to 1W. But I'm sure you'd have figured that out
PDQ.

You then stick the (unzipped) .hgt files through '3dem',
http://dl.winsite.com/bin/downl?10500000036165
and twist them into UTM co-ordinates .. they then make a nice
background for Oziexplorer and similar (unless you are somewhere flat,
in which case you'll have nothing to see).

If you live somewhere too bumpy too wet or with snow and ice lying,
all of which wreak havoc with the radar, you may want to put the dem
through BLACKART first to fix the null areas.
http://www.terrainmap.com/rm38.html

Quoted message said:

If you don't mind a big download after all, there is a program
'dem2topo'
http://people.uleth.ca/~brad.gom/dem2topo
which claims it will turn the Digital Elevation Models from 3DEM into
contours, although the Virtual machine to run it is a 167Mbyte download,
so I haven't tried it yet.

I see that they will send you it on CD :-)
--
Phil Cook looking north over the park to the "Westminster Gasworks"

Bitstring <[email hidden]>, from the
wonderful person Phil Cook <[email hidden]> said

Quoted message said:

GSV Three Minds in a Can said:

For those of you bored with Worldwind (or without a fast enough
connection to download it all), you can download the individual (degree
square) SRTM (Shuttle Radar Topography Mission) tiles from:
ftp://e0dps01u.ecs.nasa.gov/srtm/Eurasia

The name of the file tells you where the bottom left corner is eg N52W02
covers 52N to 53N, 2W to 1W. But I'm sure you'd have figured that out
PDQ.

You then stick the (unzipped) .hgt files through '3dem',
http://dl.winsite.com/bin/downl?10500000036165
and twist them into UTM co-ordinates .. they then make a nice
background for Oziexplorer and similar (unless you are somewhere flat,
in which case you'll have nothing to see).

If you live somewhere too bumpy too wet or with snow and ice lying,
all of which wreak havoc with the radar, you may want to put the dem
through BLACKART first to fix the null areas.
http://www.terrainmap.com/rm38.html

None of that in South Shropshire, thankfully. *grin*

Quoted message said:

Quoted message said:

If you don't mind a big download after all, there is a program
'dem2topo'
http://people.uleth.ca/~brad.gom/dem2topo
which claims it will turn the Digital Elevation Models from 3DEM into
contours, although the Virtual machine to run it is a 167Mbyte download,
so I haven't tried it yet.

I see that they will send you it on CD :-)

Yeah, but I'm not that patient! The download did get here (about 8 hours
over night) and it works like a hose. Just overlaid the contours on the
Tracklogs 1:25k digital data, and the match is pretty good .. much
better than the match I can get by manually digitizing 1947 (feet!)
contours .. you wouldn't believe how =few= spot heights those early OS
surveyors could use to imagine a whole raft on contour data. 8>.

Wrinkle: when you save GeoTIFF data from 3Dem you =must= be in
degrees/minutes mode. If you save in degrees/decimals the .tif file will
not be read by Dem2Topo.

Now if only there was an equally slick way of getting
roads/rivers/forests, the OS would be out of business ...

Oh and 'Thanks Again' NASA.

--
GSV Three Minds in a Can
Outgoing Msgs are Turing Tested,and indistinguishable from human typing.

Bitstring <[email hidden]>, from the
wonderful person Phil Cook <[email hidden]> said

Quoted message said:

GSV Three Minds in a Can said:

For those of you bored with Worldwind (or without a fast enough
connection to download it all), you can download the individual (degree
square) SRTM (Shuttle Radar Topography Mission) tiles from:
ftp://e0dps01u.ecs.nasa.gov/srtm/Eurasia

The name of the file tells you where the bottom left corner is eg N52W02
covers 52N to 53N, 2W to 1W. But I'm sure you'd have figured that out
PDQ.

You then stick the (unzipped) .hgt files through '3dem',
http://dl.winsite.com/bin/downl?10500000036165
and twist them into UTM co-ordinates .. they then make a nice
background for Oziexplorer and similar (unless you are somewhere flat,
in which case you'll have nothing to see).

If you live somewhere too bumpy too wet or with snow and ice lying,
all of which wreak havoc with the radar, you may want to put the dem
through BLACKART first to fix the null areas.
http://www.terrainmap.com/rm38.html

None of that in South Shropshire, thankfully. *grin*

Quoted message said:

Quoted message said:

If you don't mind a big download after all, there is a program
'dem2topo'
http://people.uleth.ca/~brad.gom/dem2topo
which claims it will turn the Digital Elevation Models from 3DEM into
contours, although the Virtual machine to run it is a 167Mbyte download,
so I haven't tried it yet.

I see that they will send you it on CD :-)

Yeah, but I'm not that patient! The download did get here (about 8 hours
over night) and it works like a hose. Just overlaid the contours on the
Tracklogs 1:25k digital data, and the match is pretty good .. much
better than the match I can get by manually digitizing 1947 (feet!)
contours .. you wouldn't believe how =few= spot heights those early OS
surveyors could use to imagine a whole raft on contour data. 8>.

Wrinkle: when you save GeoTIFF data from 3Dem you =must= be in
degrees/minutes mode. If you save in degrees/decimals the .tif file will
not be read by Dem2Topo.

Now if only there was an equally slick way of getting
roads/rivers/forests, the OS would be out of business ...

Oh and 'Thanks Again' NASA.

--
GSV Three Minds in a Can
Outgoing Msgs are Turing Tested,and indistinguishable from human typing.

Bitstring <[email hidden]>, from the wonderful person
GSV Three Minds in a Can <[email hidden]> said
<snip>

Quoted message said:

Wrinkle: when you save GeoTIFF data from 3Dem you =must= be in
degrees/minutes mode. If you save in degrees/decimals the .tif file
will not be read by Dem2Topo.

Correction: what seem to cause a problem is converting the SRTM data to
UTM projection before saving a geoTIFF from 3DEM. If you save the
original data (which is stretched sideways, on account of our
latititude) it works fine (and Dem2Topo does the conversion back to
'nice square grid' during the processing to get contours).
--
GSV Three Minds in a Can
Outgoing Msgs are Turing Tested,and indistinguishable from human typing.