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Lord_Rixk

SRTM Coast holes

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Hi Guys:I am trying to import SRTM-4 data into fly 2, by means of transforming the original .tif file into a .bin then (bin2ras) to .ras (taking in consideration the correct value of 6000nbr (its a 5 degrees by 5 degrees file)the files are already patched of holes in the land side (which looks really good), but the coastal areas are awfully grafted (something that NASA seems to acknowledge in their FAQ page) I have tried to fill the holes by means of 3DEM or even VTBuilder (cant use srtmfill, since I cant produce a .hgt file) but still I am left with huge cliffs where there should be a smooth beach.the files come on the formats .tiff, .hdr, .tfw, .asc and .pjr In the original files the sea has an altitude of -10mts, -57mts or even -151mts, I reset the sea value to 0mts, and then tried again (with and without going through the hole filling process) and still there are vertical gaps of at least -11kmt (up from -28kmts!!) where the sea meets the land.Would it better to try to smooth the entire coast strip (10 degrees) after it becomes a .trn file? or else is there anyway I can combine the sea values from gtpo30 files? (by the way there is a mask file in .tif format, but it only highlights the areas patched inland)is there a cheap way out of this? ...global mapper is out of the Equation (it costs US$350)any ideas?

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No worries...sortedafter a good night sleep I found the answer in VTBuilder.and just for the record, in case anyone else get stuck in the same problem, the way to patch the holes at sea level in the SRTM-4 files is to first remove the range of unwanted elevations (i.e. -151.00 -1.00) that leaves your ocean with an elevation of 0mts, and then to set all unknown areas to 0. don't patch any remaining holes with VTbuilder. use 3dem instead (but using small areas 1 at the time, rather than the entire file at once (it gives you a better finished product).and voila.now another question... can these srtm files be in anyway changed to dem 1 deg? is there anyway I can implement the shading relief option for scenery outside USA?thanksDan

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No worries...sortedafter a good night sleep I found the answer in VTBuilder.and just for the record, in case anyone else get stuck in the same problem, the way to patch the holes at sea level in the SRTM-4 files is to first remove the range of unwanted elevations (i.e. -151.00 -1.00) that leaves your ocean with an elevation of 0mts, and then to set all unknown areas to 0. don't patch any remaining holes with VTbuilder. use 3dem instead (but using small areas 1 at the time, rather than the entire file at once (it gives you a better finished product).and voila.now another question... can these srtm files be in anyway changed to dem 1 deg? is there anyway I can implement the shading relief option for scenery outside USA?thanksDan
Hi Dan - As far as I can recall, TerraScene can only do the shading if you are able to get a hold of the 7.5 DEM files. Randall Rocke may know of something, but the only way I know of achieving something along your line of questioning is a method of colorizing satellite photos per Fonchy's methods. I think somewhere in the file library you may be able to find a tutorial on a method of colorizing. But far as using terraScene, I do not think it possible.Cheers!

___________________________

Kenneth E Wood Jr  🌪️🌩️

ex AG1, USN (14yr Vet) Weather Foecaster

 

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Thanks, I had almost given up on that.I will look up his tutorial in the library.Dan
Well, though I have no artistic ability, I think I had downloaded the tutorial at one time. I'll go through my file and see if I can find anything. It may have been left in either the developers forum or this one as a message as well. If you have not done so, you might can try a search through both forums on that.As a further thought - wondering if the SRTM data can be resampled to 7.5 and used in that light? Might be a question for the scenery forum further up the list... ;-)Cheers!

___________________________

Kenneth E Wood Jr  🌪️🌩️

ex AG1, USN (14yr Vet) Weather Foecaster

 

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