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machi
I finished my first good image of Uranus.
Planet is colorized from three filtered images (orange, green, blue).
Slightly brownish color of rings is entirely artificial.
Hungry4info
That's pretty neat, ^.^, though the rings look a bit bright =o.
machi
Yes, rings look bright, because their brightness is enhanced.
Rings are in fact barely visible.
Original exposition times were 15.36 s for rings images (clear filter) and 0.72 (blue filter), 1.44 (green filter), 5.76 (orange filter) for Uranus images.
Despite of these exp. times, rings were still very dark (much darker than Uranus).
machi
Probably highest resolution image of Uranus with some details (~12 km/pix).
Color from green, violet and synthetised images.
antipode
Hey thats very nice! Has this dataset been ignored because it was assumed nothing much could be squeezed out of it?

P
machi
Possibly. But I think, that lots of information is still hidden in these images. And for long time, these are best images of Uranus. sad.gif
tedstryk
Great work! I have always focused on the moons, never the planet.
antipode
Ever since the original data was released, it always seemed to me that the response was 'big bland boring ball......oooh look at that pretty Miranda over there!' Now that the planet has gone through equinox and we have Hubble and Keck etc, we know better, but still the popular assumption is that the planet is just a big featureless fuzzy ball.

Given that you are right, and that we are likely to see Neptune close up (Argo?) before we see Uranus close up, I for one am very interested in what you find in this dataset. Maybe with a bit of suitable processing it will surprise us all!

P
elakdawalla
If you haven't seen it, you should check out Bjorn Jonsson's version of a Voyager Uranus image, posted with lots of his comments about processing. The key thing of interest in reply to antipode's post is that he found no features in the images that were significant enough to make it worthwhile to rotate the three frames in 3D space to align them before creating the color composite.

Also, regardless of whether Argo is selected, I think Neptune will be visited again before Uranus, because of Triton.
Bjorn Jonsson
QUOTE (elakdawalla @ Jan 9 2010, 09:59 PM) *
If you haven't seen it, you should check out Bjorn Jonsson's version of a Voyager Uranus image, posted with lots of his comments about processing. The key thing of interest in reply to antipode's post is that he found no features in the images that were significant enough to make it worthwhile to rotate the three frames in 3D space to align them before creating the color composite.

This is different from my Jupiter, Saturn and Neptune processing where I usually rotate the images in 3D space. For Uranus I didn't see the need for that as the features are very low contrast in OR, even more low contrast in GR and not visible at all in BL.

Uranus is no less interesting than Neptune in my opinion. Being visually bland doesn't make a planet uninteresting, it just makes it more difficult to explore. Comparing Uranus and the other the other big 3 there are interesting differences, for example Jupiter, Saturn and Neptune radiate significantly more energy into space than they receive from the sun while Uranus doesn't - it radiates hardly any excess heat. And with the exception of Triton, Uranus' satellite system is actually more interesting than Neptune's. Comparison with the Cassini results at Saturn would be interesting.

I have sometimes been a bit frustrated that Voyager 2 couldn't be launched a bit later (or technology developed faster) because then it could have carried a CCD camera sensitive to near-IR. The amount of visible details increases greatly with wavelength (comparing OR and BL there is a big difference) so I suspect Uranus would look highly interesting to a Cassini (or even Galileo) style imaging system in the near-IR.

QUOTE (machi @ Jan 7 2010, 06:14 PM) *
Probably highest resolution image of Uranus with some details (~12 km/pix).
Color from green, violet and synthetised images.

This is extremly interesting, possibly the most interesting Voyager 2 image I have ever seen of Uranus. Now I wonder if there are any images of comparable resolution extending further 'down' and thus showing the bright feature better...
machi
I have seen Bjorn Jonnsson's image of Uranus and in fact, I use this image as color ethalon smile.gif

Uranus or Neptune? Don't forget on Uranus Orbiter! Team from JPL (also APL?) has mission scenario within New Frontiers budget. They planning solar! powered orbiter.

QUOTE
Now I wonder if there are any images of comparable resolution extending further 'down' and thus showing the bright feature better...

Probably no one in PDS online archive.
Bjorn Jonsson
It's actually quite interesting to attempt to squeeze out some details from these images but having worked mainly on Cassini images recently the image quality really sucks. Here is a quick and dirty version of image C2682833.IMQ:

Click to view attachment

Some details are visible as well as various processing artifacts and noise. In particular, the concentric ellipses are processing artifacts. This is an orange filter image from directory URANUS\C2682XXX on Voyager volume 2 (the most interesting images are probably in this directory and the directories immediately preceding and following it). The orange filtered images seem to contain the greatest amount of details but some details are also visible in the green images.

Someone should probably be able to come up with an improved version of this one.
Hungry4info
QUOTE (machi @ Jan 9 2010, 04:34 PM) *
They planning solar! powered orbiter.

Lol...

How big of an array?
stevesliva
QUOTE (Bjorn Jonsson @ Jan 9 2010, 10:47 PM) *
In particular, the concentric ellipses are processing artifacts.


Pity. I was just convincing myself that the second ring was hexagonal.
Stefan
QUOTE (Bjorn Jonsson @ Jan 10 2010, 03:47 AM) *
Someone should probably be able to come up with an improved version of this one.

Here's my take on that image (WAC green filter image 26828.33):

Click to view attachment

I think the only real feature is that bunch of clouds at the bottom.
machi
I was wrong! Is one image with slightly higher resolution, but photographed by Voyager 2 before image, which I posted above. But in this image is surface actually closer, so resolution is 11.5 km/pix compared to 11.7 km/pix in picture above.

And something to Uranus orbiter:
http://www.lpi.usra.edu/decadal/opag/UranusOrbiter_v7.pdf
http://www.lpi.usra.edu/decadal/opag/Uranu..._v7_Authors.pdf
http://spacepolicyonline.com/pages/images/...20Sat%20Sci.pdf

Online presentation (with audio) is somewhere too, but I don't know where.
machi
Best image of Uranus south pole. Circular feature is real (some details not). Nearly horizontal lines are artifacts from flatfielding.
stevesliva
The slightly lighter core inside the darker second ring could be faceted like the Saturn hexagon. But any sort of blips at single 60-degree intervals from each other is enough to make part of a blurry circle look like part of a hexagon.

Pretty cool to see structure there, though.
machi
Effectively highest resolution view from any of Voyagers. Two shots after well known Miranda mosaic images. NAC frames over one WAC frame. Color is artificial, but very close to real. It's based on the HST photometry. Resolution is 280 m/pix.
Decepticon
Wow! Love your work. smile.gif
machi
Thanks Decepticon! tongue.gif

And new image from Uranus system - moon Ariel. Resolution of this stereopair is around 1.55 km/pix.

machi
Moon Ariel resampled at 1 km/pix (real resolution ~ 1.2 km/pix).
Stefan
Stunning!
ugordan
Nice work, keep it coming!
antipode
WOW! That's the best look at that moon I've ever seen!

Actually its so good I'm looking at that dramatic resurfacing in a new light. There's a real paucity of medium to large craters in that image?

P
machi
Stefan and Ugordan: Thanks!

Antipode:
Actually yes, surface of Ariel is relatively young. I don't know about any large crater on that moon. Even medium craters are scarce.
Moreover some parts looks like surface of Enceladus. In terms of geologic activity, Ariel is perhaps between Enceladus and Dione.
tedstryk
Great work! That is the mosaic I based my first LPSC conference on http://www.planetary.org/blog/article/00001362/
DrShank
QUOTE (tedstryk @ Aug 16 2010, 07:55 PM) *
Great work! That is the mosaic I based my first LPSC conference on http://www.planetary.org/blog/article/00001362/



always nice to see a continued interest in the verdant orb.

dont forget these nice bits, including topography:
http://stereomoons.blogspot.com/2009/08/more-ariel.html
machi
QUOTE (tedstryk @ Aug 17 2010, 02:55 AM) *
Great work! That is the mosaic I based my first LPSC conference on http://www.planetary.org/blog/article/00001362/


Yes, I know about this, more of your images are in this topic http://www.unmannedspaceflight.com/index.php?showtopic=3932 .
My favourite is your "combo" image, but now, I don't know exact adress.


QUOTE (DrShank @ Aug 17 2010, 03:01 PM) *
dont forget these nice bits, including topography:
http://stereomoons.blogspot.com/2009/08/more-ariel.html


This is something new for me. I know your work on galilean satellites, saturnian satellites, Miranda and Triton, but I missed Ariel. I especially love black and white topography maps!

"New" images of Umbriel. Image data were resampled to 3 km/pix and 5 km/pix (clear-clear-violet-green sequence) and combined together. Real resolution is 5.16 km/pix and 9.67 km/pix (multicolor sequence).
machi
Three images of Titania. All resampled from original resolution 6.7 km/pix, 4.6 km/pix and 3.4 km/pix.
tedstryk
Very nice work.
antipode
Ditto.

Im enjoying this thread, and enjoying the better press Uranus is finally getting lately (jokes aside, I think the active equinox atmosphere has helped silence the 'totally bland' press the planet has had since 1986).

Back to the moons. I wonder (Wunda? rolleyes.gif ) how many decades it will be before we get a better peek at Umbriel's strange Wunda? Looks very Iapetaen.

P
ugordan
QUOTE (machi @ Aug 19 2010, 02:08 AM) *
Three images of Titania.

Is the color shift to red/pink near the terminator real or an artifact?
machi
Ted: Thanks!

Antipode:
I'm always enjoying work with Uranus moons, I hope this is another small piece of work which leads to support new mission to these strange lands.
"Wunda? Looks very Iapetaen" I think so too smile.gif.

Ugordan:
All three images shares same color data from medium resolution image.
I used different processing technique to highest resolution image which leads to slightly bigger color differences.
So I think color shift is real, but slightly more enhanced than on another two images (and terminator regio isn't so good visible on these two images).
tedstryk
I have also noticed the color shift.
ugordan
It looks like a calibration artifact at first, but then if you look closer it looks like an albedo feature as it extends clockwise all the way to the sunlit limb at 5 o'clock. I think that's the most color variation I've seen on Uranus' moons.
Stu
You see? THIS is why I love UMSF so much... You Image Mages delve into the misty archives, drop the old, forgotten images dumped there into your cauldrons, give a good stir and whumpf! out come amazing new views of these distant worlds... ohmy.gif

Many thanks for sharing these beautiful pics, guys.
machi
Ugordan, Tedstryk:
In case of color shift near the terminator, I think that's combination of imperfections of calibration (which are more evident at low brightness level) and real surface color. I looked at maps and redder hemisphere is around 90° longitude. I think it's the leading hemisphere.

Stu:
Image Mage, nice phrase smile.gif
"forgotten images dumped there into your cauldrons"
My secret ingredient is bat's ear but keep it under your hat smile.gif

Last in set - Oberon.
Resampled at 3 km/pix. Real resolution 7 km/pix.
ugordan
Here's a color version of Titania using calibrated data from the PDS rings node:
Click to view attachment

Left is gamma-correct, right is contrast enhanced.
While that calibrated data set is known to have calibration issues and is not the greatest quality Voyager ISS data set in the world, it appears to be missing the color shift around the terminator.

Taking a quick look in green+violet (as well as using clear as an effectively 460 nm filter) color of all the moons, Miranda, Ariel and Umbriel appear to be effectively grey (Umbriel the most), while Oberon and Titania have that slight brownish tint to them.
sariondil
Machi´s version of the Oberon data set can be used to add a tiny bit of coverage along the terminator of Steve Albers´ map. I assume the color processing is different and just roughly adjusted the brightness.
While I´m at it, here´s a quick reprojection of the Titania nightside coverage dicovered by Ted Stryk onto Steve´s map (looks slightly mismatched, but dayside features line up in this position).
machi
Anaglyph of Titania. It's based on synthetic frame between last two high resolution Voyager images of Titania.
Edges were removed.
algorimancer
QUOTE (machi @ Apr 13 2011, 10:01 AM) *
Anaglyph of Titania.

The fractures certainly stand out. A bit more topographic height than I would have expected. Neat.
machi
Cross-eye stereo image of Titania. Synthetic image is more precise than that one in previous anaglyph.
Resampled to ~2 km/pix. Edges were cropped from synthetic image.
nprev
Daniel, you're a wizard. These are AMAZING.
Bjorn Jonsson
Agreed, this is amazing. Interestingly the anaglyph reveals that the surface is a bit depressed farther away from the big fracture than can be easily seen in the original imagery.

I want a Uranus orbiter! ;-)
nprev
I noticed that the (bear with me on the terminology here because this is Uranus & everything's tilted 98 deg) 'north polar' area seems depressed as well 'above' the large crater in the crosseyed pair.

Interesting little world among many there, well worth further investigation. Sure hope I live that long.
machi
Thanks!

I see many topographic details, but one must be careful about interpretation. For example some "details" can be simply artifacts from reseau marks.
But I made simple comparison with Titania topography obtained by photoclinometry from article
Large impact features on middle-sized icy satellites from Moore, Schenk, Bruesch, Asphaug and McKinnon (Icarus 171, 421-443)
and it looks very similar to their DEM of Gertrude regio.

This is cross-eye "stereo quaternion" made by same method. First pair is in principle same as my first cross-eye of Titania,
others are new for a little different perspective.
Two outer images are "original" (processed) images from Voyager, others are synthetic.
Edges are distorted, but I preserve them now for completeness (in cross-eye images, their aren't so disturbing).

EDIT: Anaglyph version is here.
ilbasso
Wow! The anaglyph version looks almost like a hologram. The images appear to rotate slightly when you move your head from side to side. Beautiful work!
Paolo
some new, cool infrared images of Uranus and Neptune
http://www.space.com/13086-photos-neptune-...red-images.html
stevesliva
One thing that got mentioned on twitter but not there was the obvious eccentricity of Uranus's rings. Pretty neat.
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