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Holger

Mesh north of 60

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Guest sgreenwood

Well, yes.GTOPO30 (30 arcsec) data is available for the world in mostly 50x40 degree files. I've converted all of these directly to mesh with an LOD of 7 (305.8m), which means most of the files are quite large.The improvement over the default mesh, in areas where the default mesh resolution (LOD) is lower, varies from subtle to rather nice in some areas. I have a sample file (~55MB ;) ) for the area in the map below available for testing at:www.fs-traveler.com/cgi-bin/gtopo30-w100n90.ziphttp://forums.avsim.com/user_files/85719.gifThe full 2-CD set (854MB) is available at: http://www.fs-traveler.com/products-c.shtmlPerhaps others can help with info about higher resolution mesh for smaller areas. Cheers,Steve

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Hi Steve,Maybe I'm wrong, but I read somewhere that Microsoft used GTOPO30 to build the FS9 mesh. If this is the case, there should be no improvement in using again these source data, even if the resulting mesh is calculated at LOD7.Can someone confirm this ?ThanksAlain

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Guest sgreenwood

Yes, I've seen that claim as well, but I don't believe MS has ever confirmed it, and the differences I see are difficult to attribute to differences in LOD alone.We can't hope for much in the way of accuracy when using 30 arcsec data. Oversampling the data using an LOD of 7 does increase the detail, however, and this additional detail makes the terrain more interesting and probably does not detract much from the limited accuracy of the original data..Here are a three images showing the difference in FS2004.I suggest saving them and then toggling between them to see how much more detail is added using the gtopo30 mesh. (No claims about accuracy, but after flying with the gtopo30 mesh for a while, I never went back to the default.)I also include an image using srtm 3 arcsec mesh for comparison. It is certainly more detailed yet (LOD9) and presumably more accurate as well.Location: N35 51.14, E51 30.07, 10288 ft, hdg 043 (because srtm data/mesh is available here for comparison)Default mesh:http://forums.avsim.net/user_files/85789.jpgGTOPO30:http://forums.avsim.net/user_files/85790.jpgSRTM 3 arcsec:http://forums.avsim.net/user_files/85791.jpgIt looks to me like the GTOPO30 mesh is more like the 3 arcsec mesh than it is like the default. (Better than I expected, actually, but this does seem to vary with location!)Steve

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Howdy,more information regarding the original question:Jim Keir has uploaded a mesh/scenery package of the Brunt Ice Shelf, Antarctica: http://www.jimkeir.co.uk/FlightSim/scenery.htmlFreddy Wilhelmsen and others are working on a mesh/scenery package for northern Norway: http://forums.avsim.net/dcboard.php?az=sho...ing_type=searchGilles Gauthier has uploaded a terrain mesh of northeastern Canada (Nunavut); file names nunavut8a.zip to nunavut8d.zip here in the library.In general, though, flying at very high latitudes can be a bit of a dizzying experience in FS9, due to the way the "flat" lat/long "projection" works, or rather, doesn't work. See this thread: http://forums.avsim.net/dcboard.php?az=sho...ing_type=searchCheers, Holger

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