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If could someone kindly point me to where I can find middle east and north of africa meshes.ThanksFido

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Hi Fido:For northern Africa (Morocco, Algieria, Tunesia), Nanucq Faitman has released mesh files based on DTED1 data, which is about the same resolution as SRTM (3-arcsec, or ~90-m). They are very nice and available here in the file library. Just do a search for his name.For the Middle East, no high-res mesh exists (to the best of my knowledge). However, Svante Wedel put out a "lightweight" mesh for Europe, which includes the Middle East (eurmed-1.zip, here in the library). That mesh is made from "oversampled" 30-arcsec data but Svante is very up front about this and his read-me file is a good summary of the pros and cons of trying to "beef up" low-res source data.As Justin has pointed out, hopefully we'll soon have SRTM coverage of Africa and the Middle East.Cheers, HolgerEdit: Holy cow! - Nanucq's mesh files have disappeared, his site, faitmain.com, isn't active anymore either, and francesim.com dropped the files too! His Morocco mesh is still available at flightsim.com (fm_maroc.zip) but none of the others. Anyone knows what happened there?

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Guest jimkeir

Hi.I had a similar problem last week looking for his mesh - I eventually found the England mesh on (I think) a French site.Just out of interest, what data d'you think he based that on? Looked *remarkably* similar to the Lago mesh to me.Regards,Jim Keir

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Howdy:I remember that Nanucq had started offering his mesh files as payware compilation discs but I couldn't find any payware under his name either.As for source data, his read-me files state "made in LOD9 (76.4m) based on DTED1 DATA". Interestingly, DTED1 data are classified by their provider (the US military) and are not available to the public, free or for sale: http://www.globalsecurity.org/intell/systems/dted.htmHere's an interesting quote from one of John Child's online articles:"NIMA has never released its DTED1 series of DEM data and in fact is doing its best to block NASA from releasing 30m SRTM data from the Space Shuttle. (Quote from the NASA SRTM website: "Following the events of Sept. 11, 2001 our project partners in the National Imagery and Mapping Agency have requested that NASA and JPL not distribute any SRTM data to the scientific community or the public, including shaded relief maps or other visualizations. We look forward to this restriction being lifted soon so data may be made publicly available.")" --> http://spatialnews.geocomm.com/features/childs4/LAGO claims that the Terramesh series is made from DTED0 and VMAP0/1 data but I really don't think anyone could generate that detail and accuracy from 900-m (30-arcsec) source data and a few vectors (the VMAP data). Perhaps Nanucq and his fellow FranceSim.com mesh designer Thierry Pignot, who is credited by LAGO as their mesh programmer, "found" and shared the same DTED1 source data? Well, that makes for an interesting "detective story" but I won't go there ;-) I don't own the Terramesh series but continue to use some of Nanucq's files. Both mesh series provide great improvements over the lame default terrain - and that's what counts, IMHO!Cheers, Holger

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Guest Ozzie

Hi FidoTwo more names could give you some of what you are afterJosiah HautGiovanni Miduri - sometimes called BavarelloHope this helps

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Guest digger

Actually, good meshes ARE available for most of the Middle East and part of North Africa (Egypt and a bit of Libya). You can check it out at http://edcsns17.cr.usgs.gov/srtm/. The format is SRTM DTED1 (3 arc second). Unfortunately, it's not free.Last week I ordered the CD for Area37, which covers a sizable part of Egypt (the Nile Valley and the Red Sea coasts, mainly), and it cost me $40 plus mailing costs. The detail is excellent, but the existing FS landclasses are worthless in the case of Egypt and will have to be done all over again.>If could someone kindly point me to where I can find middle>east and north of africa meshes.>>Thanks>>Fido

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Hi Willem:interesting find! According to the website, these are "cleaned up" SRTM data (except for voids 20 pixels and larger). I wonder whether that means that the second stage of SRTM releases will all be commercial only?Cheers, HolgerP.S.: I'll look for the satellite data you requested

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HI Holger,The "small voids" are easily-enough taken care of. It's large voids that are the problems, but this Level 1 stuff doesn't do anything about them. What's the use of paying $40 for a CD when I can fix the small voids myself anyway, I say.-------Justinhttp://www.fsgenesis.netHigh Quality Scenery for FS200x


________________

Justin - Toposim

http://www.toposim.net

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Hi Justin:I agree about the voids - in fact, it's very strange that they would leave those as is. As far as I know, the final version was supposed to be generated from two separate passes of the radar signal, thus eliminating spikes and most voids. Maybe this stuff then isn't that final version.On the other hand, the payware product does include quite a few post-processing steps, some of which would be difficult to achieve without auxiliary data. Here's the relevent part from the docs:"After NASA/JPL completes the raw data processing, NGA performs quality assurance checks on the JPL SRTM data and then carries out several additional finishing steps. Spikes and wells in the data are detected and voided out if they exceed 100 meters compared to surrounding elevations. Small voids (16 contiguous posts or less) are filled by interpolation of surrounding elevations. Large voids are left in the data. Water bodies are depicted in the SRTM DTED

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Guest digger

Hi Holger,Thanks for looking at the satellite data.The DTED files may be 'cleaned up', but I can confirm they still contain a lot of holes, small and big. I don't have enough experience to judge how this compares with the freely available SRTM data for the Americas and Eurasia, but from what I've seen I have the impression that there's hardly any difference. A good deal of the voids can be eliminated with MicroDEM, but I guess I'll have to use Blackart or a similar program to tackle the larger voids.Just to clear up any possible misunderstandings: I didn't pay for these data because they are 'cleaned up'. There's just no other way to get them.Willem

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