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Voyager mosaics and images of Jupiter, A fresh look at some ancient stuff
Bjorn Jonsson
post Aug 20 2010, 05:47 PM
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Thanks to modern computers and software the old, 'official' Voyager Jupiter images can be reprocessed into something much better. There is also a lot of Voyager data there that was never processed into color composites and/or mosaics (or at least it has not appeared on the WWW). With proper processing the apparent image quality approaches the quality of the Cassini images but needless to say the wavelength coverage is (vastly) inferior.

I have recently been taking a close look at the high resolution Voyager 1 images, i.e. the images obtained in early March 1979. This is going to result in some new and/or reprocessed mosaics. The first one is now complete and I'm working on another one.

The image below is a 12 image mosaic (12 orange + 12 violet + 12 synthetic green images). The images were obtained on March 2, 1979 at a range of 4.3 million km. The first image (C1629045.IMQ) was obtained at 05:09:23 and the last one (C1629131.IMQ) at 05:46:11. The resolution is roughly 43 km/pixel.

Attached Image


The raw images were calibrated, reprojected to simple cylindrical projection, mosaicked and then rendered using a typical viewing geometry (there is no such thing as a "correct viewing geometry" because the images were obtained over a 37 minute period with Jupiter rotating). I then fixed the color balance. I still haven't 'standardized' how I process the Voyager color. I wasn't completely satisfied with the color I got using an approach similar to what's described in another thread but I think the color could be improved a bit. The final step was to sharpen the resulting image a bit, mainly to compensate for all of the resampling that the previous processing steps required.

This image shows lots of features: The Great Red Spot and one of the three white ovals present during the Voyager flybys, smaller spots, scallopped belt/zone boundaries, gravity waves, a bright equatorial plume and the dusky south polar region.

I don't think I'm bragging by saying that this is probably the best Voyager 1 Jupiter mosaic that I know of, mainly because of its size (12 images).

I will be posting more Jupiter stuff in this thread in the coming days/weeks, both mosaics and interesting images (and needless to say, others are welcome to post images and mosaics as well).
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DrShank
post Sep 4 2010, 04:22 PM
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beauty! would you call this close to natural color now?

the voyager cameras were quite good for the time and Ive gotten lots of mileage out of the images. the big difference was the lack of infrared capability, which allows you to look deeper into the atmosphere and see thermal updrafts and hot lavas (on io that is).


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Bjorn Jonsson
post Sep 5 2010, 11:01 PM
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QUOTE (DrShank @ Sep 4 2010, 04:22 PM) *
beauty! would you call this close to natural color now?

The upper one should be fairly close to natural color but this is subjective. It might be a bit too reddish but I'm not sure. After some channel mixing I processed it to make the oval SSE of the GRS roughly white.

A few notes on the mosaics and on images I have noticed in the Voyager dataset:

(1) As should be obvious I have been looking at lots of high-res Voyager images of Jupiter recently. When doing this I have come across several images that show interesting features that I had not noticed before. An example (processed to increase contrast and sharpness):

Attached Image

And a wide angle context image shuttered at the same time:
Attached Image


The features near the top of the image are interesting. These images where obtained on March 4, 1979 at a range of 1.3 million km from Jupiter's center.

Another example (processed to increase contrast and sharpness):

Attached Image

And a context image:
Attached Image


The features (clouds?) at upper right in the narrow angle image look somewhat weird. They are located near (435,375) in the context image. The images were obtained on March 5, 1979 at a range of 630,000 km from Jupiter's center.

(2) I noticed an interesting comment in several images in a brown barge imaging sequence. For example in image C1635958.IMQ:

"ATMOS DYNAMICS 3X2 NA GR MOSAIC OF BARGE, STEREOSCOPIC WITH 16359.50 - 60.07"

This seems to have been an attempt to image Jupiter in stereo - I don't think I'm misunderstanding anything here. However, I don't think imaging Jupiter in stereo using a single spacecraft would work due to cloud motions. Two spacecraft are a different story so here's today's crazy idea: Imaging parts of Jupiter in stereo if both NASA and ESA send spacecraft there simultaneously. I'm not sure it would work though - it requires high resolution and I'm not sure ESA's JGO spacecraft is going to be capable of that due to its distance from Jupiter and maybe due to its camera as well.

(3) I haven't been able to confirm that it is indeed vertical relief and/or shadows that is visble in my mosaic. I've been looking for scientific papers and I haven't found any but I haven't searched very carefully. I also did some simple 3D test renders to see which cloud thickness and altitude might reproduce the appearance of the clouds in the mosaic but the results are inconclusive. Still this looks a lot like vertical relief and it should be noted that cloud shadows are visible in high-phase Voyager images of Jupiter. It would be interesting if someone here knew something about this topic. Also see the cloud shadow thread which has a hi-res image showing what might be shadows or vertical relief.

(4) I'm in the early stages of starting work on yet another mosaic and it's going to be a bit different from the ones I have posted here because OGV is available, not just OV. Actually there is a huge amount of Voyager stuff I'd like to process but this takes a lot of time if high quality results are desired. In particular, the lack of accurate camera pointing angles is a constant source of frustration and requires me to reverse engineer this information for every image. Fortunately, the spacecraft location is available and that data seems accurate - without it this would be even more time consuming.
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tedstryk
post Sep 6 2010, 01:48 AM
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QUOTE (Bjorn Jonsson @ Sep 6 2010, 12:01 AM) *
In particular, the lack of accurate camera pointing angles is a constant source of frustration and requires me to reverse engineer this information for every image. Fortunately, the spacecraft location is available and that data seems accurate - without it this would be even more time consuming.


So true. When I was at the New Horizons team meeting in December, I was asked if I used the camera pointing information for my work. I had to be honest - only in situations where I could not ascertain the pointing by studying the image. When it could be done, determining the pointing from the image was significantly more accurate (though much more time consuming).


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Posts in this topic
- Bjorn Jonsson   Voyager mosaics and images of Jupiter   Aug 20 2010, 05:47 PM
- - Drkskywxlt   Fantastic pic! Did you use ISIS? If so, what...   Aug 20 2010, 05:50 PM
|- - Bjorn Jonsson   QUOTE (Drkskywxlt @ Aug 20 2010, 05:50 PM...   Aug 25 2010, 03:39 PM
|- - tedstryk   QUOTE (Bjorn Jonsson @ Aug 25 2010, 04:39...   Aug 27 2010, 12:53 AM
|- - Ian R   Bjorn, I neglected to congratulate you on an absol...   Aug 29 2010, 09:06 AM
- - ugordan   QUOTE (Bjorn Jonsson @ Aug 20 2010, 07:47...   Aug 20 2010, 06:00 PM
- - CAP-Team   Wow! That's stunning!   Aug 20 2010, 07:54 PM
- - Decepticon   This is wonderful stuff! Its so nice to see t...   Aug 20 2010, 08:02 PM
|- - tedstryk   Awesome. Voyager images are quite good once you r...   Aug 20 2010, 10:08 PM
- - PDP8E   Bjorn, S T U N N I N G thank you!   Aug 20 2010, 11:51 PM
- - machi   Fantastic result Bjorn! I think, that it's...   Aug 21 2010, 06:12 AM
- - tasp   You're throwing meat in the tiger cage. We wa...   Aug 21 2010, 02:39 PM
- - antipode   Golly. I spent a good 15 minutes just wandering ar...   Aug 21 2010, 11:10 PM
- - Juramike   Really nice job! This is beautiful!   Aug 21 2010, 11:48 PM
- - nprev   Absolutely hypnotic. I've looked at it several...   Aug 22 2010, 12:24 AM
- - Juramike   Taking Bjorn's awesome image above as "re...   Aug 22 2010, 04:20 PM
- - Bjorn Jonsson   A new, big mosaic of Voyager 1 images, this time s...   Sep 1 2010, 10:21 PM
- - elakdawalla   Wow.   Sep 1 2010, 10:41 PM
- - ElkGroveDan   Oh my.   Sep 1 2010, 11:06 PM
- - Hungry4info   Goodness O_o.   Sep 1 2010, 11:54 PM
- - nprev   RE: Voyager mosaics and images of Jupiter   Sep 2 2010, 12:17 AM
- - Juramike   Whoa! The detail in that is A M A Z I N G ...   Sep 2 2010, 12:37 AM
- - Stu   That's outrageously brilliant, Bjorn. That ima...   Sep 2 2010, 05:20 AM
- - Explorer1   Holy.... holy! And I thought the Jupiter mos...   Sep 2 2010, 05:28 AM
- - Phil Stooke   Brilliant work! Phil   Sep 3 2010, 11:48 AM
- - ilbasso   One gets the impression of a "wall of clouds...   Sep 3 2010, 01:51 PM
- - jasedm   To echo comments above, this is astonishingly good...   Sep 3 2010, 09:59 PM
- - eoincampbell   Beautiful quality of detail. Congratulations! ...   Sep 3 2010, 10:28 PM
- - Ian R   Good gravy! I now officially have Jupiter-envy...   Sep 4 2010, 01:03 AM
- - DrShank   beauty! would you call this close to natural ...   Sep 4 2010, 04:22 PM
|- - Bjorn Jonsson   QUOTE (DrShank @ Sep 4 2010, 04:22 PM) be...   Sep 5 2010, 11:01 PM
|- - tedstryk   QUOTE (Bjorn Jonsson @ Sep 6 2010, 12:01 ...   Sep 6 2010, 01:48 AM
|- - DrShank   QUOTE (tedstryk @ Sep 5 2010, 07:48 PM) S...   Sep 10 2010, 10:19 PM
|- - tedstryk   I found the pointing information for the Neptune i...   Sep 11 2010, 01:04 AM
|- - DrShank   QUOTE (tedstryk @ Sep 10 2010, 07:04 PM) ...   Sep 11 2010, 01:10 AM
|- - tedstryk   OK, so you do have to correct the data somewhat. ...   Sep 11 2010, 01:14 AM
|- - elakdawalla   QUOTE (DrShank @ Sep 10 2010, 06:10 PM) ....   Sep 11 2010, 03:08 AM
- - volcanopele   Substitute Cassini for Voyager 2, and that's h...   Sep 11 2010, 03:29 AM
- - Phil Stooke   Perhaps the most important question here is, will ...   Sep 11 2010, 02:14 PM
|- - DrShank   all my work, especially the stereo stuff requires ...   Sep 12 2010, 06:59 AM
|- - Bjorn Jonsson   QUOTE (DrShank @ Sep 12 2010, 06:59 AM) m...   Sep 13 2010, 12:15 AM
- - Ian R   QUOTE (Bjorn Jonsson @ Sep 13 2010, 01:15...   Sep 13 2010, 09:08 AM
|- - Bjorn Jonsson   QUOTE (Ian R @ Sep 13 2010, 09:08 AM) it ...   Sep 13 2010, 09:41 AM
|- - tedstryk   Paul, I'm really glad to hear you are doing th...   Sep 13 2010, 02:15 PM
- - DrShank   Ted, typically, one or two active team members (Ca...   Sep 13 2010, 03:05 PM
|- - tedstryk   How do you reconstruct it then? The only way I ha...   Sep 13 2010, 03:41 PM
- - Ian R   These versions are only 'early drafts', mi...   Sep 13 2010, 05:41 PM
|- - ugordan   Nice, both the images and the videos. I can apprec...   Sep 13 2010, 05:46 PM
|- - Ian R   QUOTE (ugordan @ Sep 13 2010, 06:46 PM) N...   Oct 4 2010, 08:43 PM
- - machi   IanR: Wonderfull job! It looks very promisingl...   Sep 13 2010, 09:22 PM
- - Bjorn Jonsson   My movie now consists of exactly two frames that l...   Sep 14 2010, 12:01 AM
- - elakdawalla   Can't wait for the other 98 frames   Sep 14 2010, 01:56 AM
- - Stu   Woah... BA's picked up on your GRS image! ...   Sep 27 2010, 02:13 PM
- - Bjorn Jonsson   Here is a preliminary version of a Voyager 1 movie...   Sep 28 2010, 12:59 AM
- - nprev   Utterly. Beautiful.   Sep 28 2010, 02:11 AM
|- - tedstryk   Wow, that is truly amazing! I forgot just how...   Sep 28 2010, 09:47 AM
- - Ian R   Fantastic work, Bjorn! As someone who has ...   Sep 29 2010, 01:53 AM
- - elakdawalla   Now the red spot mosaic has been reposted on wired...   Sep 29 2010, 01:58 AM
- - brellis   Every 1,000 times I see or read something amazing ...   Sep 29 2010, 03:29 AM
- - Ian R   Here's another GRS-centred time-lapse movie of...   Sep 30 2010, 03:21 PM
- - Ian R   This is a contemporary-produced version of the mov...   Sep 30 2010, 04:24 PM
- - machi   GRS from Voyager 1. Resampled at 5 km/pix, origina...   Oct 4 2010, 05:09 AM
- - Astro0   OMG!   Oct 4 2010, 05:23 AM
- - Stu   No, sorry, I don't believe it. You've give...   Oct 4 2010, 05:36 AM
- - ElkGroveDan   Holy smokes. Maybe it's just my mind interpre...   Oct 4 2010, 02:05 PM
- - Hungry4info   Wow. Nice! That's very impressive!   Oct 4 2010, 04:33 PM
- - machi   Stu: I think, that even with TARDIS, I would be co...   Oct 4 2010, 04:51 PM
- - Ian R   Hot Diggity Dog! That's marvellous Daniel....   Oct 4 2010, 08:30 PM
- - ZLD   I took the image and did my own processing on it; ...   Oct 6 2010, 03:58 AM
- - Astro0   ZLD, my take is that your 'shadow' is in f...   Oct 6 2010, 05:55 AM
- - machi   ZLD, Astro0: Yes, "shadow" is variance ...   Oct 6 2010, 07:37 AM
- - machi   It's possible use both green and violet images...   Oct 6 2010, 12:45 PM
|- - ZLD   That is quite impressive. Can you send me a link ...   Oct 6 2010, 07:22 PM
- - elakdawalla   My favorite search tool for Voyager and other oute...   Oct 6 2010, 07:50 PM
- - machi   ZLD: I have almost all image data from Voyager do...   Oct 7 2010, 09:48 AM
- - Ian R   Here's a frame from the Voyager 1 approach mov...   Nov 8 2010, 07:03 PM
- - Ian R   Bjorn, I hope you don't mind, but I decided t...   Nov 9 2010, 12:45 PM
|- - dilo   Ian, could you upload a slightly compressed versio...   Nov 9 2010, 05:26 PM
|- - Bjorn Jonsson   QUOTE (Ian R @ Nov 9 2010, 12:45 PM) Bjor...   Nov 9 2010, 08:57 PM
- - elakdawalla   Here you go, I've hosted Ian's tweened ver...   Nov 9 2010, 05:28 PM
|- - tedstryk   Wow!   Nov 9 2010, 08:45 PM
|- - dilo   QUOTE (elakdawalla @ Nov 9 2010, 06:28 PM...   Nov 10 2010, 02:28 PM
- - machi   Fantastic! Jupiter looks like if he's ali...   Nov 9 2010, 09:58 PM
- - elakdawalla   Well, since Bjorn started with 16 images with the ...   Nov 10 2010, 05:15 PM
|- - dilo   Thanks Emily!   Nov 10 2010, 08:07 PM
- - Ian R   Morning all! I used the MSU Frame Rate Con...   Nov 11 2010, 07:14 AM
- - Ian R   Here's a couple of 'fixed longitude' s...   Nov 19 2010, 04:13 AM
- - machi   Wonderfull animation Ian! Finally I finished ...   Nov 20 2010, 04:30 PM
- - Bjorn Jonsson   I have just finished a completely new mosaic of th...   Nov 23 2010, 10:08 PM
- - ilbasso   No words...should have sent a poet... That is a s...   Nov 23 2010, 11:14 PM
- - nprev   Stu surely would have volunteered! Stunnin...   Nov 24 2010, 12:50 AM
|- - tedstryk   Simply amazing!   Nov 24 2010, 02:32 AM
- - ilbasso   I had to put this up on my 42" HDTV to begin ...   Nov 24 2010, 04:17 AM
- - Stu   Every time you post one of your images, Bjorn, it...   Nov 24 2010, 06:54 AM
- - ZLD   Astounding Bjorn! I really love your work. I...   Nov 24 2010, 07:56 AM
- - nprev   To be fair, Galileo did very well considering the ...   Nov 24 2010, 08:21 AM
|- - tedstryk   QUOTE (nprev @ Nov 24 2010, 08:21 AM) To ...   Nov 25 2010, 03:34 AM
- - machi   Excellent (as always)!   Nov 24 2010, 02:32 PM
- - Juramike   Wow....that is awesome! Nice work, Bjorn...   Nov 24 2010, 04:41 PM
- - Juramike   The more I stare at this the more I see! (Lik...   Nov 24 2010, 04:48 PM
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