SRTM30 for whole Earth

[Guest vlada stoje]

Hi all,the latest news SRTM30 at the address http://edcsgs9.cr.usgs.gov/pub/data/srtm/ perhaps could be a disappointment, when everybody is waiting the 3 arc sec data, but there are also pros. One point of this 30 arc sec data is the average of 100 points of the prepared 3 arc sec data, so the precision is better as in the old Gtopo30. Moreover, there are interesting files, containing the difference between Gtopo30 and SRTM30 and also the number of valid 3 arc sec points for every new 30 arc sec average (ranging 0

[PanosG 2]

What file(s) must download of this Index?http://forums.avsim.net/user_files/33134.jpghttp://jdtllc.com/images/RCsupporter.jpgPanos Georgotas

[Guest vlada stoje]

Hi Panos,it depends what information you are searching, I like the num files, see the small piece from the e020n40.numCheersVladaExtract from the documentation:Extension Contents--------- -------- DEM digital elevation model data HDR header file for DEM DMW world file STX statistics file PRJ projection information file GIF shaded relief image SRC source map SCH header file for source mapIn addition several additional files are included using these extensions:Extension Contents--------- -------- dif difference between SRTM30 and GTOPO30 jpg color coded shaded relief image num number of valid point included in the 10x10 average std standard deviation of the elevations used in the average

[PanosG 2]

Hello Vlada,With GTOPO30 I used 4 *.dem and 4 *.hdr files, to make a mesh terrain for whole Greece, see bellow.E020n40.demE020n90.demW020n40.demW020n90.demE020n40.hdrE020n90.hdrW020n40.hdrW020n90.hdrNow my question is, what files (extensions) must I download from SRTM30 ftp site?http://jdtllc.com/images/RCsupporter.jpgPanos Georgotas

[Guest vlada stoje]

Hello Panos,the naming system is exactly the same. Perhaps the difference between the elevations in Gtopo30 and SRTM30 is not important for FS scenery, but the num files contain the simplified information about the pattern of the voids in the prepared 3 arc sec data already for whole Earth. I think that for the smaller dark places the interpolation of the 3 arc sec data will be sufficient and for the large dark places is possible to prepare the detailed data from different sources in advance. Btw. four Gtopo30 tiles for one country, terrific! (I know it, Slovakia needed 2 tiles w020n90 and e020n90)Cheers