On my list. I also have to do an evaluation of the SRTM's 30m resolution. Some are also available for the PH. Will check if this is available in the public.
On Sat, Oct 22, 2011 at 10:20 PM, Eugene Alvin Villar <sea...@gmail.com> wrote: > Hi maning. Well, why don't you do your evaluation again for V2? It's > supposed to be much more improved than v1 since they collected a lot > more data. :) > > On Sat, Oct 22, 2011 at 10:05 PM, maning sambale > <emmanuel.samb...@gmail.com> wrote: >> We had an internal evaluation of this dataset (v1) a while back, it >> has a several data issues such as too much noise, molehills and >> unknown depressions in our test area. >> >> We concluded that as per V1, it is better to use the SRTM dataset. >> >> And another thing consider: >> >> "To let people know before they spend a lot of time downloading the new >> ASTER GDEM: this new data has a grid spacing of 1 arcsecond (~30 m), but >> the actual resolution is closer to about 120 m because they used a 9x9 >> pixel matching window on the ASTER 15 m images to extract the >> topography. The resolution and accuracy in most locations is not as good >> as the SRTM 3-arcesecond DEM, but it does have useful data in many of >> the locations where SRTM has voids." >> >> I don't know if this has improved already for V2. >> >> >> On Sat, Oct 22, 2011 at 9:27 PM, Eugene Alvin Villar <sea...@gmail.com> >> wrote: >>> Hi guys, >>> >>> Exciting map geek news! Version 2 of the ASTER GDEM data[1] has just been >>> officially released for civilian use![2] >>> >>> Some of you may have been aware of the ASTER GDEM map data that was released >>> back in 2009 (Version 1). This data contains the 3D elevation of 99% of the >>> earth at a resolution of 30 meters. This is 9 times more dense than the >>> SRTM3 data (90m resolution) that is the default data used in Google Earth. >>> However, version 1 was only released as raw data only fit for scientific >>> research. In version 2, they have clean the data and it can now be used by >>> the general public. :) >>> >>> I once played with GTOPO30 and SRTM3 data to create topographic maps[3] and >>> I think the ASTER data would be interesting to play around with. :) >>> >>> [1] http://www.gdem.aster.ersdac.or.jp/ >>> [2] http://www.wired.co.uk/news/archive/2011-10/19/nasa-elevation-map >>> [3] http://vaes9.codedgraphic.com/posts/topomaps_using_srtm3_data >>> >> >> -- >> cheers, >> maning > -- cheers, maning ------------------------------------------------------ "Freedom is still the most radical idea of all" -N.Branden wiki: http://esambale.wikispaces.com/ blog: http://epsg4253.wordpress.com/ ------------------------------------------------------ _______________________________________________ talk-ph mailing list talk-ph@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk-ph
