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PostPosted: Mon, 25-01-16, 21:36 GMT 
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Many of you (myself included) have probably been wondering:
Where is all the data from the Chang'e lunar missions?

Here they are:
http://www.planetary.org/blogs/guest-bl ... board.html


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PostPosted: Tue, 26-01-16, 9:25 GMT 
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dirkpitt wrote:
Many of you (myself included) have probably been wondering:
Where is all the data from the Chang'e lunar missions?

Here they are:
http://www.planetary.org/blogs/guest-bl ... board.html


Many thanks, Dawoon. Things were much less organized when I downloaded Chang'e 2 data about 2 years ago...The data had to be downloaded from a site with Chinese writing and a numerical address. No problem for you, but all I could read in some places was "Chang'e'. And after a short while the server became unavailable. ;-)

Here is some info after my first contacts with the huge Chang'e 2 texture (213.4k x 106.6k). Perhaps it is still somewhat useful.
viewtopic.php?f=6&t=424

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PostPosted: Wed, 27-01-16, 2:31 GMT 
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I hope the mosaics have been geodetically corrected since then, so they can be used to upgrade the WAC reflectance map.


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PostPosted: Thu, 28-01-16, 8:57 GMT 
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I'm still struggling to figure out how to download a high-resolution cylindrical map from the Chinese PDS.
It seems I might need to sign up for an account, but the registration form keeps timing out.


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PostPosted: Fri, 29-01-16, 7:46 GMT 
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i think it is this
http://translate.google.com/translate?p ... hapce2.jsp

http://moon.bao.ac.cn/ceweb/datasrv/shapce2.jsp

the link is on the Planetary Society site
http://www.planetary.org/blogs/guest-bl ... board.html

" pds2isis" opens them after renaming the img file
BUT
you need to manually FIX the broken lbl file

or

QGis ( uses GDAL ) can open the img file and use gdal to warp it from the "LambertConformal" to "SimpleCylindrical"

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PostPosted: Fri, 29-01-16, 11:53 GMT 
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It seems more work is required before things would align properly (tiles F008 and F009 reprojected to Moon 2000):

Attachment:
geo_error.png
geo_error.png [ 428.91 KiB | Viewed 1845 times ]


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PostPosted: Tue, 02-02-16, 12:07 GMT 
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Emily Lakdawalla just recently put a lot of Chang'e 3 data online:
http://www.planetary.org/blogs/emily-la ... hange.html

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PostPosted: Mon, 15-02-16, 1:06 GMT 
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I found a paper on block adjusting (bundle adjusting) Chang'e 2 images using LOLA data (PDF download):

http://www.lsgi.polyu.edu.hk/staff/Bo.W ... d_lola.pdf

The authors use it to generate a DEM, but bundle adjustment is also required to get you a good image mosaic.

In order to reproduce the results of the paper, we would need something like SPICE kernels for the mission to obtain the internal and external orientation parameters of the camera. Not sure where these are yet...

EDIT: The paper says such kernels aren't published.
So what the authors did was use 10-20 LOLA points as ground control points per Chang'e 2 stereo pair as inputs to indirectly determine the camera external orientation parameters. These parameters were then refined through bundle adjustment.


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PostPosted: Mon, 15-02-16, 16:21 GMT 
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That "Pyramid Rock" looks like a silicate reef...

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PostPosted: Sat, 20-02-16, 17:58 GMT 
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*Sigh*

Looks like the 50m mosaic hasn't been updated with better geodetic correction :(

Attachment:
change_alignment.png
change_alignment.png [ 369.6 KiB | Viewed 1700 times ]


I guess the only hope is purchasing the original CCD swaths @ 4k pixels/deg from China, and hope at least seven different planets align to convince them to do so, so a proper assembly can finally be done...


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PostPosted: Mon, 22-02-16, 5:38 GMT 
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Geometric correction of lunar images (or of any other body apart from Earth for that matter) to get a good mosaic is really hard due to the lack of reliable positioning data.
At KARI we're planning to use either LOLA or SLDEM (2013? 2015?) as a control network, but it's really not an ideal situation...


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