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SRTM Version2 1x1 degree files

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Great news, Dick, thanks very much! By coincidence, I was just about to head over there this morning. File sizes are much smaller - a welcome relief for my very slow modem.Best regards.Luis

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Right, very nice overall. Very little fiddling with the files, although there are still voids and values below sea level (but, you will have to look hard to find them.)Using Emerson's great program, it took about 30 seconds to make a bgl, so easy.However, I wonder if these files still have the half-pixel shift. I am having some difficulty telling.On this file, there definitely seems to be a shift, comparted to the default LOD 8 mesh (it is probably SRTM as well):http://forums.avsim.net/user_files/129646.gifBut, just a short distance away, there does not seem to be any shift:http://forums.avsim.net/user_files/129647.gifAnybody know the present status of this? By the way, this is the research-grade data, I assume.Best regards.Luis

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Hi all,Thanks Dick for pointing the link! Luis, this isn

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Thank you, Vlada. I checked with the previous "dirty" version of the data, and, as you say, there is no shift.I suppose this means that we must pull out Todd Klaus' Terrascene for creating water masks. Strange to think that he was doing this all of 5 years ago.It occurs to me, and perhaps to others, that now that there is a mutually-consistant source of altitude and water data with almost global coverage that soon all our techniques of the past few years will start to gather dust. The next version of FS will most likely incorporate this data, meaning that we shall have nothing to do except to add a little detail to the terrain. We shall have no other recourse but to... gasp, go flying!Best regards.Luis

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Hi Luis,Thanks for the tips! I quickly upgraded the fGIS to the latest free version, still cant see the elevations of the parts of rivers and also in the exported dxf file there are still only the X,Y data, no Z, but I will try more in fGIS and other programs.CheersVlada

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Hello,Dick, thank you for the link.Vlada, maybe try Microdem and overlay the vectors. There is some kind of 3D view and video animation. Are you looking for this? Or, do you want to calculate the z value from the dem data?Luis, I played today a little bit.I think, the data SWBD (a very good job!) can be used. And we can use it in FS9. (I don not know the anomalies for overlaying to the

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Hi all,Horst and Luis, thanks for the advice! I will try it, I was curious, if when running with the cursor by the river, we could see the changing altitude of the river, if the shapefile is 3D?Comparing research-grade v1 with the JPL v2, there is visible slight blur effect. I tried model it with the low-pass filter (x,x,x/x,1-8x,x/x,x,x) with the result (1,1,1/1,10,1/1,1,1) (dividing factor 18). I don

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Yikes, very sorry, Vlada. I can be somewhat dense, especially early in the morning before I have had my coffee, which is usually the time when I stop by here.I once saw a free program, WinTopo, that reads raster and writes vector, including elevation values. I do not have it, nor have I ever tried it, since this is of no use to me. But, maybe it can lead you to what you want.Best regards.Luis

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Nice GIF picture Vlada.I see loss of info (by smoothing) and some data shifting (as a side effect), even on elevated areas (non water bodies). It seems that every elevation post has been modified, not only water bordering terrain as I thought. :-(

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Hello Luis,??This is only an overlay 3arc Srtm Dem and the Srtm water body data (SWBD).You can use tools like Microdem or other.And the SWBD seems to be done from the 1arc Data, because this is the shoreline from a European lake.But will this be a nice shoreline in the Sim?The

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Hi Horst,thanks for the tips, I tried upgrade the nonregistered Arcv2cad 4.0 and it even alloves again process 10 big shapefiles and moreover it writes directly the bln x,y,z files, so the DXF2XYZ isnt necessary.The ability to read the x,y,z rivers in SBuilder would be wonderful, but lets Luis Sa relax on holidays!Thanks again,CheersVlada Stoje

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Hi,Could you send me the latest free version of fgis or link to download it? I have only version from june 2005. It is very useful program for me and the only is freeware.Best regards.Jacek

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Hi Jacek,I also love this program but I have to learn a lot in this field! My latest upgrade is 2005, September 13 (fGIS_Setup.exe with the size 6946930 :(. If you have interest for this older developmental freeware version, send me your address at stoje$volny.czCheersVlada

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It's working today Wed 5th, thanks for the link.There is also another source for this data via NASA Worldwind whole earth viewer but it's in BIL format. It is downloaded along with the visible Landsat 7 image tiles when you zoom in, or with a Tile Downloader.I have been creating photorealistic scenery with the image tiles and use a spreadsheet macro to create INF files to process the tiles with Resample and Imagetool. I have modified the spreadsheet to reference the mesh BIL tiles as well to be able to patch a few areas that had voids I was unable to correct when I made OZmesh covering NZ.The holdup at the moment is that the dataset seems to be unavailable so have not yet been able to do a test run. I have levels 0 - 5 and need to get level 7 to work with. This dataset would have been made with version 1 SRTM I guess but it must have been patched because there seems to be no voids in it.Andy

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I was able to download the Worldwind SRTM BIL tiles I needed and resampled them into Fsim mesh.The tiles are 150 x 150 so there are about 49 per deg. (7 x 7) and are in Int16 LSB format. I finished up using -99999 as null cell value because it came up in an error message during resample. I also had to revert to Ver. 1001 of resample.exe with tmfcompress and tmftobgl.The spreadsheet with the macro I use to write the multisource inf files is in Quatro Pro wb3 format if anyone want's it but I don't know if converting it to Excel etc will work, but it should give a good idea of how I did it. I think I can attach it as a zip to a post if anyone is interested.Andy

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Major bummer! I'll have to eat my hat, it looks like it's only been interpolated and is pretty crap. I had not been able to check it in Worldwind due to the download problems I had and had based my expectation on the level 5 tiles I had been viewing(Maybe I'll try them but the resolution won't be that hot). Back to the drawing board I guess.The offer of the spreadsheet still stands. Hear is what I got for my trouble.http://forums.avsim.net/user_files/146616.jpg

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