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Venus Map with Feature Names
JRehling
post Mar 20 2013, 05:30 PM
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This is downright heroic, Machi. I'd like to think that a map like this could get someone thinking about the need to go back to this world, which looks wonderfully new in your work. Incredible.
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machi
post Mar 21 2013, 01:07 PM
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Thanks!

Yes, I hope so too.
Venus or especially its surface is still not well understood and available data are not comparable to that, which we have for the Moon or Mars.
For example, Magellan's altimeter had pretty low resolution.
Every altimetric measurement covers area 100 to 1000 km2 large.
For comparison, Mars Global Surveyor MOLA's laser spot had size under 0.1 km2.


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Robotbeat
post Mar 25 2013, 04:32 PM
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Thanks so much! Incredibly professional, the best I've seen of any Venus map!

Do you have a source for the elevation data? Ideally I'm looking for something like a greyscale heightmap image (PNG or something), but I'm curious as to what your source was.
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JohnVV
post Mar 25 2013, 05:08 PM
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QUOTE
Do you have a source for the elevation data? Ideally I'm looking for something like a greyscale heightmap image (PNG or something), but I'm curious as to what your source was.

i can post the data i used
in simple cylindrical projection
from 2048 x1024 up to 65536x32768 pixels in size
but it is 16 bit unsigned little endian

a 4096x2048 8 bit normalized ( 0 to 255 ) png


the remapped "browse" image
http://pds-geosciences.wustl.edu/mgn/mgn-v...002/gtdr/sinus/
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Robotbeat
post Mar 26 2013, 12:53 AM
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Thank you! I plan on using it to make a 3d model (for printing out on Shapeways). If/when I finish it, I'll share it here.
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JohnVV
post Mar 26 2013, 01:01 AM
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QUOTE
Thank you! I plan on using it to make a 3d model (for printing out on Shapeways). If/when I finish it, I'll share it here.

then you WILL need a 16 bit image to start with
there is a PDS ( .img) Blender 2.6 import tool that takes a PDS DEM and converts it to a sphere

or you can use say a perl script to convert the 2d x,y,z( px value) into 3d x,y,z
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Robotbeat
post Mar 26 2013, 01:09 AM
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Thanks, but I think this will work for now. 256 levels isn't too bad for just a bumpy sphere (it will be tessellated anyway); it worked fine for Mars:
http://www.thingiverse.com/thing:26311

EDIT: For clarity, I didn't make that Mars object.
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machi
post Mar 26 2013, 02:02 AM
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Robotbeat:
If you want elevation data as DEM, then I recommend you DEMs from MG_3003 dataset.
Or you can download shape file, which Mark Wieczorek did.


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machi
post Nov 28 2013, 08:40 AM
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Because of the practically unlimited account which I have now on the Flickr, I've uploaded full version of my topographic map of Venus.
Full PDF is available here - Topographic map of Venus - PDF.



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JohnVV
post Nov 28 2013, 09:01 AM
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That PDF is 97 meg
so if you have a slow connection....




ADMIN: The version on Flickr is 57mb
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machi
post Nov 28 2013, 11:33 AM
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Yep, sorry for that. Both PDF and jpg are really big (~100 and ~60 MB).
I had problems with PDF version in Adobe Acrobat, but it works without problems in Sumatra or SMART viewer.


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nprev
post Nov 28 2013, 06:03 PM
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Fantastically detailed & dedicated work, Daniel. Spectacular!!! smile.gif


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t_oner
post Nov 28 2013, 08:22 PM
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Very beautiful and useful.
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vikingmars
post Nov 28 2013, 10:40 PM
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QUOTE (machi @ Nov 28 2013, 09:40 AM) *
Because of the practically unlimited account which I have now on the Flickr, I've uploaded full version of my topographic map of Venus.

What a GORGEOUS map !!! CONGRATULATIONS !!!
Thanks to you Machi, we have also solved an old mistery about Venus : its maximum elevation is 12,177 m (on Maxwell Mountains).
Thanks a lot ! wheel.gif wheel.gif wheel.gif wheel.gif wheel.gif wheel.gif
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machi
post Nov 29 2013, 12:18 PM
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You're welcome!
Regarding to every elevation on the map, one must be careful, because Magellan's data are pretty bad in comparison with for example MGS's MOLA laser altimeter.
Resolution of radar altimeter was pretty low (one spot covers 100 - 1000 km2!) and interpretation of data in diverse terrain really isn't straightforward.
Theoretically radar is better for peaks with its threshold signal altimetry than for lowlands with complex terrain where data are sometimes really messy because of multiple reflections from terrain.
I wrote more about it on my blog, but you must use google translator.
Overall Magellan's data for Venus are comparable to Viking's data for Mars so I recommend to treat them in the same way (as data with great uncertainty).
So generally our understanding of the surface of Venus is similar as our understanding of the surface of Mars in late 70's - early 80's.


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