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PostPosted: Fri, 05-02-16, 0:26 GMT 
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Posts: 13
This add-on will be posted once I sort out the permissions and distribution logistics to get it on the Celestia Motherlode!


It was only a matter of time, but the SLDEM2013 finally got processed into a **Level 7** normal map!
This was made possible by a fellow Orbinaut, kamaz, who downloaded and downsampled 79% of the map
to 512 ppd, near its effective resolution. I cannot thank him enough for his efforts, and saving me a call from my ISP!

The map was originally 2 terabytes, but I learned its effective resolution was between 256-512ppd, likely close to a
tenth of the resolution**, as mentioned here. Since going to level 8 would only offer a marginal improvement in quality,
I opted for a level 7 normal map. I tested fridger's nmtools, and yes, they work for 131k maps! :)
Level 7 took about 30 minutes to process.

Once I saw the results in Celestia, I was blown away. I couldn't even tell the underlying texture map was only 32k!
Goes to show that a good normal map goes a long way to making a planet look awesome.

Some previews of the normal map:

Attachment:
File comment: Near Aristarchus crater
elev_preview_1.png
elev_preview_1.png [ 475.17 KiB | Viewed 1611 times ]

Attachment:
File comment: Tycho @ Level 7
tycho.jpg
tycho.jpg [ 283.39 KiB | Viewed 1611 times ]

Attachment:
File comment: Montes Jura @ Level 7
montes_jura.jpg
montes_jura.jpg [ 143.2 KiB | Viewed 1611 times ]


Compared to the GLD100:

Attachment:
File comment: GLD100 @ 64k
GLD_vs_TC_1.png
GLD_vs_TC_1.png [ 342.92 KiB | Viewed 1611 times ]

Attachment:
File comment: TC @ 64k
GLD_vs_TC_2.jpg
GLD_vs_TC_2.jpg [ 253.18 KiB | Viewed 1611 times ]


The last two images demonstrate why a ridiculous* (1.4 megapixels by 737k pixels across!) resolution is needed to
ensure a decently detailed stereo-pair-derived DTM.


*Ridiculous-res is more the rule than the exception for remote sensing ;)

**The team mentioned the effective resolution of the GLD100 was ~1km per pixel, or about a tenth of the detail of the original stereo-pairs.


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PostPosted: Tue, 09-02-16, 2:54 GMT 
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Joined: Tue, 04-09-07, 2:32 GMT
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Location: South Korea
FYI There is also SLDEM2015 which improves upon SLDEM2013. Perhaps your friend could take a look at it also?
Although it is for latitudes 60S - 60N only, the authors of the paper suggest using LOLA for the poles...


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PostPosted: Tue, 09-02-16, 4:12 GMT 
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I would have used it if not for two other points:

The LOLA ground tracks are clearly visible, which I find distracting for moon visuals:
Attachment:
File comment: LOLA ground tracks clearly visible
lola_ground_track.png
lola_ground_track.png [ 177.52 KiB | Viewed 1565 times ]


"Poorly-fit" tiles are replaced with LOLA-only data, even worse!:
Attachment:
File comment: Jarring transition to LOLA-only data
tc_lola.png
tc_lola.png [ 161.6 KiB | Viewed 1565 times ]


The overall accuracy of the SLDEM2015 is better, but I find it lacking in these areas.

I do however agree with the authors on using LOLA data for the poles, but I found the
cutoff for the SLDEM2015 to be way too much. Maybe if I could upload the data-reduced
DEM as a resource for others to improve upon?


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PostPosted: Fri, 29-04-16, 21:06 GMT 
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Joined: Tue, 04-09-07, 2:32 GMT
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Location: South Korea
Were the issues ever sorted out with getting SLDEM2013 on the Motherlode?
I think this would be great addon for people to try out.


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PostPosted: Tue, 03-05-16, 4:05 GMT 
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Joined: Tue, 04-09-07, 21:55 GMT
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Location: N 42.38846 W 83.45456
i do not think so

as far as i know the LAST and only 128k ( 131072x 65538) is my venus map
i was informed NOT to upload more by the people at ibiblio

but that was a while ago so....

_________________
"I don't pitch Linux to my friends, I let Microsoft do that for me."
Using OpenSUSE 42.1 & Scientific Linux 6.7


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PostPosted: Thu, 05-05-16, 1:33 GMT 
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If the motherlode can take another 12 gig addon, I'd be happy to upload.
If not, I could use my mega account, but bandwidth limits might limit availability.

I don't exactly how to upload to the motherlode via FTP.
Do you just use your account details there, or is there more to it?


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PostPosted: Fri, 13-05-16, 23:49 GMT 
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Joined: Tue, 04-09-07, 2:32 GMT
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Location: South Korea
Could the addon be posted as two separate addons? e.g., one for levels 0-5, another for levels 6-7


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