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[monks]

 Aye, + I imagine they collect other data too which they can use for stuff like the MODIS etc. It'd be kinda wasteful if they didn't while they were up there!

monks

[foxfiles]

To get proper results they have to image several times the complete land surface area of Earth.

There is an explanation why they have to do so at the bottom of their page here
http://www.astrium-geo.com/na/2953-first-tandem-x-coverage-completed

What is good is that they can record the full Earth many many times, so quality with accuracy will improve more and more.
As long as the SATs remain operative...

We can assume that at the end the dataset will be lower than Petas... but I wonder how big though?

[monks]

I read somewhere that they were using 3 sats now but they're using two here. Maybe them being so close together will enable them to only use two to get the accuracy.
 That is some crazy good dems there. Makes me go all fuzzy...What I'm wondering is once these come online, will better dems than SRTM 4 become freely available?

 monks

[foxfiles]

Yes you ask the good question 
I do not think that those European companies (Astrium, which belongs to EADS, which belongs to French and Deutsch Gov and Lagardere Group and others...)
will make anything freely available.
I am from Europe and when you see that our politicians have been able to crash down the fusion between EADS and BAE (British AeroSpace),
you can understand where we are here 

[foxfiles]

Monks? aren't you the ME-DEM's man? from Europe too, GB, are you?

[monks]

Thanks!- that's a good link and very informative. Yes, I think 4 is just 3 with fixes. I do share peoples' fascination and love of high quality dems- lookng at dems just does something to my head- can't explain  , and to some people, they don't even need a game to enjoy it. Having said that, having tried modelling a large "realistic" terrain I've also become more aware of what's possible. If you're not careful you can end up always chasing the next wave (higher res or whatever), and never actually releasing anything. In ME-DEM we *could*
go to 50m res, or possibly even higher but scripts would need to be rewritten and there would be delays, not least with the extra processing time. Much better to get out a version 1.0 that's as good as you could feasably make it, and accept that it ain't perfect.

monks
 

[monks]

haha!..you made me laugh "ME-DEM's man". Yes, from GB mate. You're from France I read. You seem to know a fair bit about dems and GIS stuff, sources and what not.

monks

[foxfiles]

  I'm French but I'm in Luxembourg, "crushed" between France, Germany, Belgium.
Thks from the compliment but I'm not so versed in GIS and other DEM, DTM, DSM stuff : I'm sure I'm much less skilled than you there !
I just like 3D technos, Comp Graphics, simul, games, mil. stuff and many many other things.
I'm an "old" Robotics/CAD/.... guy with eclectic interests (does eclectic means anything in English?).

 

[monks]

 They still manage to get those radio signals out though- radio Luxembourg has kinda entered the cultural psyche over here. 
 
 I'm not really skilled, just persistent.

 Yes, I can see why you would be drawn to Outerra- well I can see why anyone would, but the
 possibilities for sims in Outerra is great plus it kinda straddles a couple of territories- games and GIS.

 Eclectic, yes gotcha...is that another word that we English stole?  Sounds like could be French origin.

monks

[foxfiles]

Do you mean that you listen to Radio Lux ( RTL or RTL 2 ) in the UK?
as long as I know RTL2 in German is still diffusing good 70s/80s rock/pop songs and here they have many auditors from FR-DE-BE-NL
However I am pretty sure you have much better radios there in the UK for that kind of good music.

Anyway Luxembourg is more famous for its Fiscal and Banking system than for anything else.

Yes I fully agree about OT having great potential for GIS, real time Simul, games, etc...
I am not so interested in game engines, I'm more focused on professional applications or serious games (for example Prepar3D in flight simulation)

Please can you explain what are you doing at ME-DEM ?

Cheers - Denis

[foxfiles]

BTW I have just quickly tested the TANDEM-X sample GeoTiff from Barcelona Spain,
they say it is 10m resolution and the file can be seen and downloaded here :
http://www.astrium-geo.com/na/1194-sample-imagery

Then I imported it in GMapper, re-exported it to KMZ low res,
then made 2m vector contours lines and exported them to KML without compression.
( I must admit that it is the 1rst time that I use GMapper... so maybe I did not use it at max perfs ??)

There are funny little ridges that you can see in the blue regions : in fact they correspond to sur-elevated highways,
so when they say that is Digital Terrain Model, according to me, these man made structures should had been cleaned...

Then I wanted to test it and compare in Google Earth, so :
I imported both files in it :
I am very surprised to see that GoogleEarth terrain in that area is quite good, it seems that Earth is at or close to 10m there ?
as long as I understand GoogleEarth is using a topo source from the Catalunian Region, so the good res... and they also have "elevated roads" artefacts on their datas, 

I wanted to look to importing in OT the corresponding datas (collada importer) but unfortunately I can't, cause an issue on my old GPU...If someone could take a look, of course, the goal is absolutely not to criticize because we know what OT terrain is (resolution + fractalisation), just a question of curiosity.

Below my screen dumps related to the below procedure (GoogleEarth images zoomed proximity to the San-Climent-de-Llobregat town) :

[monks]

Luxembourg radio...yes, I think it's just a bit of a novelty- that we can pick it up! 

 We're building a dem of Middle Earth. Simple as that really. That includes textures of course, and once
the dem is released for Outerra, we hope people will add stuff to it- buildings, etc, whatever.
 We have all of the core data in Global Mapper, dem + vector maps for stuff like roads and vegetation distribution.
 It's georeffed according to what Tolkien stated in his letters, Minas Tirith = Florence, Hobbiton = Birmingham, UK.
 The dem is currently at 100m res. Not much point in going larger than that until we get the first version out
the door. Also, Outerra fills in the small scale details which helps greatly. One of the original objectives was to have good hydrology on the dem- that is for the main rivers on the Tolkien maps to flow correctly in a physics
sim. It's a tall order and Robes (one of our members) has written a physics sim so we can test it. It won't be possible though for all of the rivers, just potentially the main ones.


 In Global Mapper did you have the simplify contours slider set? You might want to check that that was set to 0.
 Hmm, yes, they are very straight- they're definitely not natural and they're not artifacts produced in the export.
 I've never had anything like that when using GM. So really it's a DSM. I don't see how analysts could miss those.
 Maybe this is still not an exact science. I mean they really have to cobble together full coverage dems from what's out there. It must be difficult. If it's difficult for Google, imagine what it's like for everyone else! The terrain is great though in Google- so are they using 30m res?

monks

[foxfiles]

We're building a dem of Middle Earth. Simple as that really. That includes textures of course, and once
the dem is released for Outerra, we hope people will add stuff to it- buildings, etc, whatever.

Hummm, nice project indeed !

In Global Mapper did you have the simplify contours slider set? You might want to check that that was set to 0

You're right, simplification was at a default value of 0.1 I think
I have just quickly put it at 0 and re-exported the contours, but does not change a lot

ve never had anything like that when using GM. So really it's a DSM. I don't see how analysts could miss those.

I know that this Tandem-X goetiff sample is on the Astrium website since quite long, so I suspect it comes from a very early recording without real check,
and I hope that they normally provide better 10m DTM ?

as for what I'm seeing in GoogleEarth, for that specifi location, I would say that they are at the same resolution.
If it was at 30m, they would not have the same artifacts on the roads on bridges... would they?

What is sure is that they do manage well in having different resolutions : for example their DEM in the Luxembourg area is pretty bad, I even wonder if they are at 30m here.


 

[monks]

Yes, they're early images, and if it takes up to 4 years processing them to commercial standard...! The analysis will no doubt correct those artifacts.I imagine blending between different resolutions of dem data is a bit of a nightmare- is there any evidence that Google are doing that? I thought that Google is used for some scientific work- the Google pro package? Dunno.
 Hey, do you remember NASA WorldWind? We were looking for someone to get the ME-DEM data into that because it allows user created dems (Google does not). We had some interest from a guy who works for NASA (in UK I think) a few years ago and he said it would be ok if we put it on a server there.But we did not have the dem to good enough standard- until now really.  That would have been Fab!
 We have a guy on the project who set this up. We're intending to add more map layers to it.
 http://66.172.33.110/openlayers2.html

monks

[foxfiles]

I have no sufficient time to check properly what Google Earth is doing in resolution, but I think they do have different resolutions !
If you look at Honolulu, HI, National Cemetery of the Pacific (it's inside a crater), I think they are at much better than 90m or 30m.

It is not so hard to mix various resolutions if you get the ressources to do so...

Middle Earth in OT time line is ?