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 Post subject: Re: Pluto
PostPosted: Sat, 18-07-15, 15:46 GMT 
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Celestial Phineas wrote:
t00fri wrote:
PS: you may read it yourself in your own link
http://planetpixelemporium.com/pluto.html

I didn't notice... I knew this map is not pluto, though. I didn't really know this comes out of Ganymede...
:oops: Sorry. So this is an unscientific hard work again...


Never mind.

My preference is always a (rectangular) map that does NOT contain any artwork.
Instead of using black as the color for unexplored surface regions, my preferred procedure is to use instead a color defined as the average of the colors that arose from existing data. This average can easily be obtained by blurring the known areas very strongly in The GIMP or in Photoshop. Unlike black color the resulting color is "related" to the color of the real imaging data and thus integrates smoothly in an overall visual surface map. Still, one can distinguish right away what is real information and what is unexplored terrain!

Fridger

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 Post subject: Re: Pluto
PostPosted: Sat, 18-07-15, 23:23 GMT 
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The mask strategy:
Attachment:
mask.png
mask.png [ 40.46 KiB | Viewed 1645 times ]

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 Post subject: Re: Pluto
PostPosted: Sun, 19-07-15, 0:01 GMT 
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Bjorn Jonsson over on UMSF posted a map ( very early ) of Pluto and Charon

http://www.unmannedspaceflight.com/inde ... ic=7986&hl
from the 14'th and 16'th
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 Post subject: Re: Pluto
PostPosted: Sun, 19-07-15, 12:48 GMT 
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Just to see whether I still remember how to do planetary projections and all that ;-)

I used the opensource map projection software mmps-0-1-36 and quickly generated the following views of the resulting Pluto map in celestia.Sci (using Celestia instead would also work):

[by all means, click onto images and then
use the fullscreen browser shortcut (F11 in FF)]

Attachment:
pluto_test.jpg
pluto_test.jpg [ 288.92 KiB | Viewed 1628 times ]


Attachment:
pluto_test1.jpg
pluto_test1.jpg [ 163.8 KiB | Viewed 1628 times ]


The mmps code can be downloaded from here http://www.users.globalnet.co.uk/~arcus/mmps/
Compilation under Linux or Mac Os is a matter of seconds (just hit 'make'). I use that software since many years. It is quite powerful yet easy to use.

My mmps-generated Pluto texture map from the latest photo
https://www.nasa.gov/press-release/nasa ... -encounter
has 2048x1024 pixels and of course still invokes an unexplored hemisphere...

See also the tutorials:
http://www.users.globalnet.co.uk/~arcus ... uropa.html
http://www.users.globalnet.co.uk/~arcus ... hoebe.html

Enjoy,
Fridger

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 Post subject: Re: Pluto
PostPosted: Sun, 19-07-15, 18:32 GMT 
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Here are a few more data about my generation of a 2k pluto texture map using the latest photo of Pluto (Jul 14 2015) and the mmps-0-1-36 map projection software as described in more detail in my previous post.

Have a look at this comparison picture in the first place:

[by all means, click onto images and then
use the fullscreen browser shortcut (F11 in FF)]

Attachment:
pluto_Sci.jpg
pluto_Sci.jpg [ 143.11 KiB | Viewed 1622 times ]


The Pluto photo on the left represents the input from the New Horizons probe as of a few days ago. On the right, you see a screenshot of the resulting display in celestia.Sci, adjusted to about the same size and viewing perspective.

I think, the result looks pretty similar, although I had to deduce indirectly a reference latitude of 45 degrees for the rectilinear projection.

If you want to play a bit with this Pluto texture map in Celestia, here is my 2k version for download:
+++++++++++++++++++++++++++++++++++++
2k Pluto texture map
Attachment:
plutomap0.jpg
plutomap0.jpg [ 191.74 KiB | Viewed 1618 times ]

+++++++++++++++++++++++++++++++++++++

Enjoy,
Fridger

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 Post subject: Re: Pluto
PostPosted: Tue, 28-07-15, 20:54 GMT 
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http://photojournal.jpl.nasa.gov/catalog/PIA19858

attention ! 5 MB image

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 Post subject: Re: Pluto
PostPosted: Wed, 29-07-15, 6:01 GMT 
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Thanks symaski62!

This impressive 18630 x 9315 size calls for my texture tools to make a nice VT set with coloration (GIMP) inferred from the global True Colored Pluto map above.

Fridger

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 Post subject: Re: Pluto
PostPosted: Wed, 29-07-15, 9:19 GMT 
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Hi,

couldn't resist to do some adaptations with the new (official) Pluto map
http://photojournal.jpl.nasa.gov/catalog/PIA19858
NASA wrote:
The map includes all resolved images of the surface acquired between July 7-14, 2015, at pixel resolutions ranging from 40 kilometers (24 miles) on the Charon-facing hemisphere (left and right sides of the map) to 400 meters (1,250 feet) on the anti-Charon facing hemisphere (map center).


At this time I implemented just 2 mods:

  • I auto-colorized the official map in GIMP using the previous True Color image of the full Pluto disk as a color reference.
  • I resized the resulting map to a power-of-two texture: 16384x8192 that is also suited for making VT sets. Moreover, some older graphics may not get along well with non-power-of-2 sizes.

Here is the 16k sized colored map for download:
+++++++++++++++++++++++++++++++++++++++++

16k colored Pluto texture map
Attachment:
plutomap1.jpg
plutomap1.jpg [ 8.52 MiB | Viewed 1551 times ]


As usual for my textures, the unexplored (lower) region has received a color that was obtained as the color average of the explored texture portion.
+++++++++++++++++++++++++++++++++++++++++

Finally, here are 3 hires views of the result within celestia.Sci

[by all means: click on the images and hit the browser's fullscreen key (F11 in Firefox)]

Attachment:
pluto_hires1.jpg
pluto_hires1.jpg [ 224.66 KiB | Viewed 1551 times ]


Attachment:
pluto_hires2.jpg
pluto_hires2.jpg [ 195.08 KiB | Viewed 1551 times ]


Attachment:
pluto_hires3.jpg
pluto_hires3.jpg [ 177.77 KiB | Viewed 1551 times ]


Enjoy,
Fridger

PS: Of course, for real "visual pleasure" a lot of work is still to be done in form of smoothing the transitions between adjacent texture patches. ...Like I did it years ago with my (well-known) Titan texture: My Titan Texture. Full Blog: http://www.celestialmatters.org/?q=node/28

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 Post subject: Re: Pluto
PostPosted: Wed, 29-07-15, 18:23 GMT 
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Hi all,

please don't overlook my previous post!

Backlit by the sun, Pluto’s atmosphere rings its silhouette like a luminous halo in this bw image taken by New Horizons. NASA resource

Attachment:
pluto_backlit_ring.jpg
pluto_backlit_ring.jpg [ 10.12 KiB | Viewed 1531 times ]


This post of mine is devoted to modelling this spectactular feature within Mie theory in celestia.Sci / Celestia. It provides important information about Pluto's atmosphere...

This backlit haze image was taken after the spacecraft's closest approach, when it was leaving Pluto behind with the far-away Sun illuminating its hazy atmosphere. We do remember a similar phenomenon in case of Titan....

Here is what I used for the atmosphere and Mie parameters:
Code:
        Atmosphere {
        Height      130.0                  # official value [km]
        Lower       [0.232 0.1929 0.1566]
        Upper       [0.07725 0.0643 0.0522]
        Sky         [ 0.3 0 0 ]
        }
       
        Mie              0.0001
        MieAsymmetry    -0.55
        Rayleigh   [ 0.0 0.0 0.00017 ]
        Absorption [ 0.000075 0.00030 0.00025 ]
        MieScaleHeight 39.0


Note that the measured height of the atmospheric haze amounts to 130 km above Pluto's surface in two layers. You may look up the meaning of the Mie parameters here:
viewtopic.php?f=9&t=116&start=75

Have a look at what I get with these assignments:

By all means:
[click on images and then hit the browser's fullscreen key (F11 in Firefox)]

Attachment:
pluto_atmosphere.jpg
pluto_atmosphere.jpg [ 160.3 KiB | Viewed 1531 times ]

In this front view you don't see much of the atmosphere as it should be...

In backlit configuration, however, we do reproduce this spectacular ring!
Attachment:
pluto_backlit.jpg
pluto_backlit.jpg [ 124.06 KiB | Viewed 1531 times ]


Enjoy,
Fridger

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 Post subject: Re: Pluto
PostPosted: Wed, 29-07-15, 20:08 GMT 
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do not even bother downloading the 165 Meg tiff
it was made from the 6.5 meg JPG!!!!!

the tiff has the same JPG artifacts

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 Post subject: Re: Pluto
PostPosted: Thu, 30-07-15, 8:11 GMT 
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Please don't overlook my previous post!

John Van Vliet wrote:
do not even bother downloading the 165 Meg tiff
it was made from the 6.5 meg JPG!!!!!

the tiff has the same JPG artifacts


I don't see the problem with the TIFF file. With a low download rate of only
25 Mbit/second it just takes about 50 seconds to download ~160 MB.

While artefacts may well be common to both versions (TIFF and JPG) for a variety of reasons, the color rendering may still be better in the lossless TIFF, and you can't be sure which format was first (without somebody telling you ;-) ). Yet, why should members of the graphics team be so stupid to make the official TIFF reference file from a lossy JPG format???

Fridger

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 Post subject: Re: Pluto
PostPosted: Thu, 30-07-15, 16:31 GMT 
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having the tiff's made from the jpg's has been a KNOWN issue and remarked upon on UMSF
This also has been a issue for Dawn and Rosetta .

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 Post subject: Re: Pluto
PostPosted: Thu, 30-07-15, 18:26 GMT 
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Please don't overlook my earlier posts!

John Van Vliet wrote:
having the tiff's made from the jpg's has been a KNOWN issue and remarked upon on UMSF
This also has been a issue for Dawn and Rosetta .


Sounds really odd to me: after billions of dollars spent for a space mission they don't manage to publish their official graphical reference files in lossless formats...!?

Fridger

PS: I was sure that one of the UMSF guys must have spread that info ;-)

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 Post subject: Re: Pluto
PostPosted: Fri, 31-07-15, 21:00 GMT 
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http://photojournal.jpl.nasa.gov/catalog/PIA19866

Moon Charon

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 Post subject: Re: Pluto
PostPosted: Sun, 02-08-15, 19:07 GMT 
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symaski62 wrote:
http://photojournal.jpl.nasa.gov/catalog/PIA19866

Moon Charon

Image

:)


Thanks symaski62!

While the Charon map may look easier to render in celestia.Sci/ Celestia it is NOT. When I am satisfied with my results, the Charon map will be available for download, of course...

Fridger

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