November 4, 200322 yr Commercial Member Hi all:just a few comparison shots of the first uploaded SRTM-based mesh of Europe (Sicili, Italy), by Giovanni Miduri, versus the DTED1-based mesh uploaded earlier this year by Nanucq Faitman.To be honest, I would have thought that the DTED1-based mesh would show more detail, as those source data are derived from standard geodetic procedures (photogrammetric mapping). However, it appears that the SRTM mesh with the same 3-arcsec source resolution provides slightly higher definition of detail. Whether that's due to higher accuracy or less accuracy (e.g., more noise) I can't tell, because I'm not familiar with this particular area. I'll have another look at some German sites that I know better.Interesting stuff...Cheers, Holger http://forums.avsim.net/user_files/46956.jpghttp://forums.avsim.net/user_files/46957.jpghttp://forums.avsim.net/user_files/46958.jpg
November 22, 200322 yr Holger, the first shot of Mount Pellegrino in Palermo gives me the impression that the Nanucq scenery is more realistic: the somewhat blockier looks of the mountain in Miduri's scenery may be the result of oversampling, or of the SRTM data themselves. I have tried also the new Italian scenery of Pietro Mauri (SRTM data integrated where necessary with lower resolution data) and they look better, but for instance in Gozo they display a blank area that looks like a flatten, but probably derives from an empty area of the data themselves (in Miduri's scenery in fact the looks are just the same).Largo
November 22, 200322 yr Author Commercial Member Hi Largo:thanks for the feedback - having people familiar with an area look at different mesh products is always the best "test" for accuracy. Seems like here it's another case of more apparent detail masking as accuracy. SRTM data obviously have their problems but I'd be the last one to complain about this boon of free elevation data ;-)Cheers, Holger
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