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bpk_2007
August 22nd, 2007, 02:29 PM
Mjello

I need help with using TransDEM i have downloaded DEMs for Microdem and saved them, but when i open the DEMs in TransDEM the UTM coordinate system allways starts from 0??

Is there anyway to download the DEMs directly to TransDem or other options?

Thanx in advance.

BPK

geophil
August 22nd, 2007, 03:00 PM
TransDEM can open popular DEM formats directly, without prior file format conversion in MicroDEM. (You will hardly ever need MicroDEM when working with TransDEM.) For European projects you will usually go for NASA SRTM data.

You can directly open the SRTM *.hgt.zip in TransDEM and TransDEM will do everything else. This includes necessary coordinate conversion form lat/long to UTM. SRTM data comes in geographic format, with a latitude/longitude raster.

(Opening SRTM in MicroDEM and saving again without explicit conversion will retain lat/long which TransDEM will reject.)

See also TransDEM main manual page 14 and page 37/38.

geophil

Jerker
August 22nd, 2007, 09:00 PM
G'day geophil,

Whilst we have your attention, I have a small problem with which you may be able to assist. I am trying to locate a suitable WMS server for the states of Victoria and Queensland here in Australia (along with the appropriate 'getcapabilities' URL, so that I can make use of the excellent facility provided by this feature of TransDEM. Do you know of any such web sites that may have recently 'arrived' since you wrote your Tutorial (at which time, only the one for NSW was available)?

Jerker {:)}

geophil
August 23rd, 2007, 02:33 AM
Hi Jerker,

I had collected a list of URLs for Web portals and WMS servers last year and posted this in the old forum. Unfortunately we lost this with the crash of that forum.

Here are surviving fractions of that list:
Victoria:
WMS via the US Navy proxy "GDIB": http://columbo.nrlssc.navy.mil/ogcwms/servlet/WMSServlet/Victoria_Land_Channel_Australia.wms
WGS84 only. Very slow at times.
There is also a conventional Web portal for manual georeferencing, use Vicgrid coordinates.
http://services.land.vic.gov.au/landchannel/jsp/map/InteractiveMapIntro.jsp
New South Wales
WMS: http://maps.nsw.gov.au/servlet/com.esri.wms.Esrimap?SERVICENAME=topoweb2_wms
WMS via the US Navy proxy "GDIB": http://columbo.nrlssc.navy.mil/ogcwms/servlet/WMSServlet/New_South_Wales_Australia_TopoWeb.wms
Queensland:
WMS via the US Navy proxy "GDIB": http://columbo.nrlssc.navy.mil/ogcwms/servlet/WMSServlet/Queensland_Australia_Atlas.wms
Have not used it, so can't tell anything about it.
There is also a conventional Web portal, too. No coordinates last time. URL?
South Australia:
WMS unknown.
Conventional Web portal, quite nice. URL?
Northern Territory:
WMS unknown.
Conventional Web portal. Coarse coordinates when I checked last year. URL?
West Australia:
WMS: http://atlas.walis.wa.gov.au/servlet/com.esri.wms.Esrimap
Very basic base map.
Conventional Web portal. URL?
Tasmania: ?
Australia, entire continent:
WMS: http://mapconnect.ga.gov.au/wmsconnector/com.esri.wms.Esrimap?Servicename=GDA94_MapConnect_ SDE_250kmap_WMS
WMS: http://www.ga.gov.au/bin/getmap.pl


geophil

Jerker
August 23rd, 2007, 02:55 AM
G'day geophil,

Vielen dank. Those remnants should do nicely. I shall try the links and see how things progress.

Jerker {:)}