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Emerson67

HGT Files where have they gone?

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I have started messing around with creating scenery.I read all the tutorials, and started downloading srtm data.It would seem that the new data is not in hgt format, and cannot be loaded into fsdem due to the fact that they are not hgt files.is there someway to convert the new format to hgt?

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The USGS SRTM .hgt data files were "tiles" of a specific size. They have been replaced with the seamless "finished" data (i.e. improved by taking out voids and spikes) where you can now download a box of any size (within reason)that you simply drag over the background map. When the download request window pops up you get the data as a .adf file by default but if you "modify the request" you can opt for a .bil file which is what you want. Alternatively you can convert the .adf file to .bil with a number of programs. The USGS site sometimes take many trys before accepting the download request and also the modified request. Just keep trying and it eventually seems to work.Then use Sbuilder's "bsq to bitmap converter" (works with .bil as well). Load the altidude bitmap in Sbuilder using the border coordinates that were provided as an .htm file with the download, select the LOD8 areas you want mesh for and compile to bgl. Works brilliantly (thanks to USGS and SRTM for the data and Luis Sa for Sbuilder).Scott

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Hi,Be careful with the "finished" "seamless" SRTM data.It's not quite finished or seamless... :) >>> It contains georeferencing issues e.g. data shifting <<<.So your Flight Sim terrain mesh will be displaced if you use that data "as-is". Look this quote from USGS:"The SRTM "finished" elevation dataset contains a half pixel shift. This is currently in process of being corrected. Caution should be used when doing analysis with this dataset"http://seamless.usgs.gov/Those issues have been discussed in the following thread:http://forums.avsim.net/dcboard.php?az=sho...g_id=2392&page=While the corrected "finished" data is not available, you should use the research grade data (in HGT files):ftp://e0mss21u.ecs.nasa.gov/srtmRegards,Emerson

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