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Unmanned Spaceflight.com > Mars & Missions > Past and Future
Stu
Because Emily is far, far too modest to plug this amazing work here herself, I'll do it! smile.gif You really have to check out the Planetary Society blog and see what she's done with some old Viking data - she's waved a magic wand over it and created what I think is a staggeringly beautiful image of Mars as a crescent. Go take a look at it now, but make sure you look at the enlarged image with a pillow or cushion at your feet because your jaw will plummet towards the floor when you see what she's done... ohmy.gif smile.gif
elakdawalla
Thank you Stu smile.gif Here's the direct link.

I only had time to do the single-frame images; I spent a while trying one of the mosaics but I am not happy with the color. I would love to see versions of all 11 full-disk approach images put together in color by someone who's a little better at coaxing lovely images out of gnarly old data sets, so I have made available a Zip file containing all 48 files (11 three-color sets, of which five are 2x1 mosaics). Someone please make these pretty!

--Emily
ElkGroveDan
My first thought was that those couldn't possibly be Viking images. The one at the top is more like the quality I recall. Thanks for doing these Emily. I just love it when our image wizards can pull up rough and awkward images from the past -- images some of us have vivid memories of -- and bring them closer to modern quality, as though we have returned to the same place with better equipment. (To this day, my favorites are Tedstryk's Sojourner reconstructions.)
Ken90000
They are beautiful.

I honestly thought that Viking 1 did take approach images. They were of a half-illuminated Mars.
ugordan
Wow, I didn't know this dataset even existed. Pretty awesome!

Here's my take on a mosaic. One can see vidicon-induced geometric distortions in the data and the background bias is either scattered light or dark current related. Tough to remove either way.
Click to view attachment
Stu
QUOTE (ugordan @ Aug 27 2008, 08:07 PM) *
Here's my take on a mosaic.


Seriously, I could cry looking at these images. That's it, right there, RIGHT there. My Mars. ohmy.gif

Unbelievably beautiful.


tedstryk
Emily, Gordan, excellent work. I have spent countless hours on them shortly before the crash of 2005 and lost my work (I never could bring myself to try again, and mine were not as good). The Viking 1 approach images are on PDS CD-ROM vo_1009
elakdawalla
I somehow missed those Viking 1 approach images in the index when I looked through it the first time, but you're right, there they are. They are not as good as Viking 2 -- many of them are overexposed at the limb, some more than others, and the pointing wasn't as good so fewer of the image sets are useable. All that being said, here's a link to a Zip archive containing the 9 best Viking 1 approach sets despeckled and PNGified, and attached is a color composition of the closest (and least overexposed).

--Emily
elakdawalla
...and here's one of the overexposed ones I was talking about.
tedstryk
I should also note that the other American 1970's orbiter, Mariner-9, also has an approach set. It gives a contrasting view to the Viking shots, since the dust storm was raging at the time. Also, the filter wheel was still free at the time, so the images are in color. In this shot, Valles Marineris can be faintly seen through the clouds. Edit: I replaced it with a combo of that image and one that shows Tharsis.

Click to view attachment
Ken90000
It amazes me to see this data both processed differently and with different eyes than when I first saw these images in the 70’s. Back then, that “garishly colored” image reveled many of the great discoveries of the 70’s. The volcanoes are there as well as a few clouds. The polar cap’s presence linked the spacecraft data to what we could see through our back yard telescopes.

I see the “New Millennium” Mars in the newly processed data. Those wispy clouds covering the entire illuminated disk are the same features that the rovers stare at regularly. Likewise, the pole is not just a cap of ice; it looks like a gently gathering frost of the same type that currently begins gathering around Phoenix.

I wonder how we will see this Viking data after the next fleet of probes completes its mission.
belleraphon1
Oh My!!!! These are awesome!!!!!!

Thanks Emily, Gordan, Ted and all...... love the reprocessed Mariner 9!!!!

I think I remember BW and a few of the garish color versions of the Viking approach images being published in AWST magazine back in 1976. I found the views wonderful back then. Had I seen these.... no words!!!!

Back in the 70's, Mars was quite a mystery, about to be revealed. Mars is still a mystery, even today, but these reprocessed images say 'World' when I look at them .....

Thanks all!!!!

Craig
4th rock from the sun
Here's my take on the images, trying to get something close to "real color" by adjusting gamma to 2.0 and processing the channels as follows:

B (~ 440nm) = 80% violet (410nm) + 20% green (550nm)
G (~ 510nm) = 30% red (625nm) + 70% green (550nm)
R (~ 650nm) = 100% red (625nm) - 5% green (550nm)

The actual figures are approximate, but the match the visual response of the human eye (I've seen different peak wavelengths listed, but here I'm using the same as values as on my previous Viking Lander images. They seem to work and reduce excess violet or green hues in Mars images).

I'm unsure about gamma adjustment, as I don't know if the raw data was calibrated for the vidicon actual response.

Finally, I've reduced image size by 75% and applied a slight unsharp mask.


So here's VO1
Click to view attachment Click to view attachment

And here's VO2
Click to view attachmentClick to view attachment
Gladstoner
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tedstryk
There are quite a few of them in this thread. http://www.unmannedspaceflight.com/index.p...c=3932&st=0
Gladstoner
.
elakdawalla
QUOTE (4th rock from the sun @ Aug 28 2008, 02:33 PM) *
Here's my take on the images...


Tremendous, 4th rock. If I ask you very nicely, will you do the whole set? Please? rolleyes.gif

--Emily
4th rock from the sun
As soon as time allows I'll do the full set, no problem.
Bjorn Jonsson
These new, reprocessed versions are awesome, it's remarkable how much better they are than the 'originals' back from 1976. The power of modern computers...

My feeling from observing Mars through various telescopes is that the images should be somewhat more orange though or even pinkish in some areas but this may be a contrast effect (bright Mars vs. the perfectly black sky).

There is a lot of old stuff that would benefit from reprocessing it on today's computers. I've been reprocessing some of the Voyager images of Jupiter, Saturn and Neptune with great results. Once finished I'll post these new, reprocessed versions.

And I'd just love to get my hands on the Pioneer 10 and 11 Jupiter and Saturn images in digital form. And Pioneer Venus as well.
4th rock from the sun
QUOTE (Bjorn Jonsson @ Aug 29 2008, 01:28 PM) *
My feeling from observing Mars through various telescopes is that the images should be somewhat more orange though or even pinkish in some areas but this may be a contrast effect (bright Mars vs. the perfectly black sky).


I agree completelly. No matter what method of image calibration or raw data from different missions, the resulting colors never look like the telescopic image of Mars.

I just try to go for consistency and caution in processing, so that all images have the same general hue and no color artifacts (excessive bluish clouds, for example, or an exaggerated redish cast over the darker albedo patches).
tedstryk
I have worked a lot with the moons of Uranus and Neptune, but never much with the planets themselves. I have also worked with a few fragments of Pioneer digital data (Saturn's rings, Io, and Ganymede), and I wish I could find the rest! One thing I would like to work on is some of the color stuff from early in the Mariner-9 mission. The problem is the unbelievable afterimages, something I can compensate for if I can find the limb or recognize a feature, since I can then subtract it. However, finding tri-color sets that can be properly handled is difficult. In the Mariner-9 combo I posted, the first image is a real tri-color combo, the second one is colorized based on it with a partial overlay of the polar region and Tharsis from tri-color sets closer in. Since we are getting away from Mars here, I started a new thread in a more appropriate place.

http://www.unmannedspaceflight.com/index.php?showtopic=5428
4th rock from the sun
Emily, here are VO1 approach images. This set covers a full planetary rotation, so perhaps an animation might be built out of it.

Click to view attachment Click to view attachment Click to view attachment

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When possible, I'll work on Viking 2 rolleyes.gif:-) .
Ricardo Nunes
elakdawalla
You are the man Ricardo!!

Here's the animation:
Click to view attachment

And here's the montage:
Click to view attachment

It's really quite wonderful. Thanks so much for doing the work on this.

--Emily
mhoward
That is some cool stuff, and the animation makes it even better. I find these global color views inspiring and moving.
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