texture aligment of planets

[Sternenfaenger]

Hi,
I use Celestia for quite some time.
But now I ask myself how precise is the texture alignment of the planets?
If you look at Earth everything seems allright:
If I let Celestia to go to 52.1°N, 10.5°E it looks like the location is somewhere in Germany, which is correct.
But if I let it go to 11.6o N, 269.5o W on Mars which is supposed to be Beagle 2's landing site (ESA's Mars expedition with Mars Express) the texture of the planet looks different than the one which I found on ESA's website: http://www.beagle2.com/landing/landing3.htm.
Another problem is, if I want to use another bitmap for the Mars texture how can I correct the aligment ?
Does the shadow border match the correct texture location at a certain time ?

Who knows the answer ?

Thx, & have a happy new year 2004.

[Harry]

It looks perfect for me, but you may need a higher resolution texture which shows craters for comparison.

Harald

[granthutchison]

Which Mars texture are you using? Some (such as Fridger's) are aligned with 180 degrees as the central meridian, instead of zero, which is the Celestia standard.

Grant

[selden]

Harry,

What Mars texture would you recommend?

So far, the textures made for Celestia that I've found don't seem to have the necessary resolution to show Isidis Planitia.

[selden]

I think I've found the source of Sternenfaenger's (and my) confusion.

The Beagle II's Web site specifies 269.5 degrees of West Longitude. Celestia measures increasing Longitude toward the East. 269.5 West = 90.5 East.

Here's a screenshot in Celestia of the region using different AltSurface selections.
The upper half displays the MOLA topographic map and the lower half is a closer view using DBrady's FlatMars.


(as usual, this links to a much larger image)

[John Van Vliet]

hi , seldon you can give my 16k mars a try but it is still a B&W . the airbrushing and colorizing arn't done yet . [/b]

[selden]

John,

Thanks!

[DBrady]

Heres a close up of the landing area on the 64k mars map i've been working on - which isnt going all that well i might add.



The large crator is the same crator as that between Isidis Doras(maybe it is Isidis Doras i'm not sure) in seldons pictures above. It is just a crop made in photoshop of the full resolution image at 66.7 percent which works out at approximately 64k.

I've made two attempts at assembling this, both can be seen at 1k level in my gallery(mars folder page3). If you look you'll see the results are quite poor. I think i'm goin to have to contrast enhance the whole thing as one big image file with netpbm and then possibly cut it up and colorise.
But i'd appreciate any suggestions anyone may have for colorising it or any aspect of making it. It's really starting to bug me now with two failed attempts(each of which takes a considerable amount of processing time).

John,
Is it possible you could make maybe a 2k or 4k map of your b&W map available for a while. I'd like to test some contrast functions in netpbm with it to see how it turns out.

[John Van Vliet]

Hi i will post a 4k B&W today
in about 30 min

john

[D.Brady]

Thanks john this should help alot.

[Sternenfaenger]

Thank you guys for your help.
I just found that Celestia is pointing to the correct texture part if I put in Beagle 2's landing coords. But how do I synchronize a texture with Celestias planet longtitude and latitude ? (sorry for my bad english) if I'd like to use another texture.
How can I check out that it matches aprox. reality ?

@selden: How do you get the marks of the craters (green text on your mars model saying e.g. "Isidis Planetia" ) ?

[selden]

Sternenfaenger,

Many maps of Mars have 0 degrees of longitude at the edge of the picture. They need to be cut in half and the halves exchanged. You can do this in many different ways -- with a paint program or with ImageMagick or with NetPGM, for example.

Celestia v1.3.1 now supports SSC files containing Locations. Several Addon lists of locations are available at http://www.shatters.net/celestia/files/locations/

Does this help?