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GregM
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Gsnorgathon
I have to admit I'm a real sucker for those "first images of..." They're a great reminder of how far we've come.

Ted Stryck has a whole slew of cool stuff.

Don P. Mitchell has some nice reprocessed Venera images.
OWW
Cool Mariner 4/6/7 ( and more ) stuff:
http://members.tripod.com/petermasek/marinerall.html

Some additinal Mariner 6/7 material:
http://cps.earth.northwestern.edu/index.html
4th rock from the sun
The problem is having the original datasets for the Pioneers and Veneras.
Otherwise one can only work from published JPGs ou images scanned from paper...
GregM
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tedstryk
Don Mitchell has gotten ahold of the original Venera surface transmissions, and is looking for the Venera 9/10 orbiter image data. His work is based on the original 9-bit imagery, which really helps the quality.
http://www.mentallandscape.com/C_CatalogVenus.htm
http://www.mentallandscape.com/C_Catalog.htm
As for the Pioneers, the best thing would be to go back to the original transmissions from the photopolarimeter scans and reconvert them into images using modern software. However, they are 6-bit, so the quality will be limited. But I imagine modern processing could do much more to fix stepping errors and the effects of spacecraft motioin - it often took 40+ minutes to scan a full image of Jupiter and Saturn!
gpurcell
QUOTE (GregM @ Apr 22 2005, 04:01 PM)
QUOTE (4th rock from the sun @ Apr 22 2005, 12:14 PM)
The problem is having the original datasets for the Pioneers and Veneras.
Otherwise one can only work from published JPGs ou images scanned from paper...
*



Yup, that's the key - the original datasets. Trying to enhance already poor existing images is kinda like trying to make a silk purse out of a sow's ear. Well, kinda, I'm sure something can be done with them to improve on them, but getting the original datasets is the proper way.

JPL, Ames, Goddard, LPL, et. al. isn't gonna do it. I was thinking of seeing some sort of relationship being set up where such legacy datasets might be passed on to expert amateurs or students working on a thesis, or some other sort of thing.

Just a hope.
*



Greg, shouldn't the original datasets be public property? Could a FOI request be filed for them?
tedstryk
In the case of the Venera data, that is a Russian thing, so it is a little trickier. The raw tapes were public domain, but again, since foreign, wouldn't be covered by FOI. Pioneer is another story. I think the problem in that case lies that, if the original transmissions even survive, they may be in an archaic format on brittle old magnetic tapes that need special equiptment to be copied, if that is even possible. Also, for Mariner IV, much of the original digital data is missing.
deglr6328
QUOTE (tedstryk @ Apr 22 2005, 08:02 PM)
In the case of the Venera data, that is a Russian thing, so it is a little trickier.  The raw tapes were public domain, but again, since foreign, wouldn't be covered by FOI.  Pioneer is another story.  I think the problem in that case lies that, if the original transmissions even survive, they may be in an archaic format on brittle old magnetic tapes that need special equiptment to be copied, if that is even possible.  Also, for Mariner IV, much of the original digital data is missing.
*


The US data shouldn't be TOO impossible to get. check here? smile.gif
tedstryk
I have not come across original Pioneer image data on the PDS. The NSSDC holds prints of all Pioneer images (made using the original processing of the data), as well as polarization data and copies of the images on microfiche. But I have no idea where the original transmissions are, if they are still around.
GregM
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edstrick
The digital data for the final versions of <most?> of the Mariner 4 mars images are available in many university engineering or aerospace department libraries. *** IN PAPER COPY! *** The Mariner Mars 1964 Project Report <in multiple volumes> contained a volume entitled something like "picture element matricies", which contained PRINTOUTS of the 200 lines and 200 samples of 6 bit data for each processed image.

I've wanted for years to scan and OCR the data and make digital versions of the images, but ..... time and effort .....

Note that the mariner 4 images were taken in alternating red and green filters, with every third image not recorded. So the pictures are: green, red, missing, red, green, missing, green, red, missing etc. The corner of one image of each red/green pair OVERLAPPED by about 100 pixels, so there is some color data from the Mariner 4 images.

All that was done for the final project report was not entirely accurate registration of the overlapping image segments and either differencing or ratioing of the images to separate color differences from brightness differences. Nothing was published in any form as a color picture from that data to my knowledge.
edstrick
Mariner 6 and 7 returned two "primary" image datasets of Mars. Far Encounter and Near Encounter. Far encounter data was narrow angle only, near encounter was alternating wide and narrow angle images. The narrow angle camera was monochrome, with <I think> a yellow filter to "cut haze", while the wide angle camera had a 4 position filter wheel. I think red/green/blue/green.

The spacecraft had dual tape recorders, derived from the Mariner 4 hardware. Unfortunately, it did *NOT* have the capability to recorde the entire dataset in digital form.

All data was recorded on an *ANALOG* tape at full resolution, after being sharpened with a circuit that enhanced fine details. Near encounter analog data was recorded after being passed through an automatic gain control filter <which totally trashed absolute intensity values for the data>. Unfortunately, the taped data was degraded by significant in-flight buildup of tape oxide on the playback <record/playback?> heads, resulting in horizontal streaky noise and banding and occassional analog dropouts in the images.

Every seventh pixel was recorded on the DIGITAL tape recorder without automatic gain control, after having the two most significant bits chopped off, which badly "contoured" the digital data. To make matters worse, the middle 1/4 or 1/5 of each image's digital data was not recorded, spectrometer data being transmitted during that gap <and between the end and beginning of each scan line as well>. BUT..... every 4'th digital pixel in the center gap was trasmitted in real time!....

The efforts to reconstruct the images were described in the Mariner 69 special report issue of the Journal of Geophysical Research, published in 1970 or early 71. They were largely successful, producing 2 versions. One was from the analog data, and was a "Maximum Discriminability" version of the data, best showing fine details. The other was radiometrically decalibrated using preflight and some inflight data on camera background and shading and spectral response, starting from the reconstructed final images. These show the real contrasts of the martian surface better, and the regional shading of the albedo markings.

The wide angle images were taken in overlapping swaths through alternating color filters, and some color information is clearly present in the images. The viewing geometry changed from frame to frame as the field of view was something like 15 degrees. I have never seen attempts to generate color images using the overlapping wide angle close encounter images.

Mariner 69 also returned a "secondary" image dataset... the every 7'th pixel data <missing that central stripe> was transmitted in real time. Most of the far encounter data includes at most slivers of the planet's limb, as the disk was within the central stripe, but Mariner 7 transmitted a unique set of WIDE ANGLE "Late Far Encounter" data with the filter wheel stepping. This data was not recorded for playback. There is a picture floating around made from this data of a half mars <cut off by that central stripe> of the Sinus Meridiani area, in color, with mabye twice or so the resolution of most any earthbased mars imagery from that period.
edstrick
Mariner Mars 1971 was to be a two spacecraft mission. One spacecraft was to be placed in a high-inclination orbit optimized for mapping, the other in an orbit optimized for "variable features" and atmosphere studies, with viewing geometry repeating closely evey few orbits. Mariner 8 went in the drink due to launch failure, and the Mariner 9 mission was redisigned to do both tasks, with the emphasis on mapping.

The imaging system was an upgrade of the Mariner 69 system, but with a new, all digital, tape recorder, capable of storing some 33'ish 800x600 or so pixel images. As before, the narrow angle camera was monochrome, with I think a yellow "haze filter". The wide angle camera had a filter wheel with a quite nice set of (I think 8) filters: Violet/Blue/Green/Red, 3 orange polarizing filters, and maybe Clear.

When Mariner 9 got to Mars in Nov 71, the greatest global dust storm *EVER* observed on the planet, which had started in Aug or Sep 71 was still essentially obscuring the entire planet. The dust was starting to settle, but... the only things visible with any contrast were 4 dark spots (the tharsis volcanos, sticking out of the dust) and the small summer south polar cap.

Mariner started it's pre-programmed mapping sequences, but it was immediately obvious that they were 3/4 useless, and a couple of makeshift interim observation sequences were developed and put in operation. A better dust storm and south polar observation sequence followed about a month after arrival, and included test mapping pics to check on atmosphere clearing. Things progressively improved and mapping was started in <I think> early January 72.

*UNFORTUNATELY*.... by then, due to a hardware failure, the filter wheel on the wide angle camera had stuck on one of the orange polarizing filter positions. The data was acceptible for mapping purposes, but any further color imaging was lost. Some color images of dark albedo markings at high southern lattitudes were generated as well as color pictures of the south polar cap and surrounding hazy atmosphere and dimly visible surface, but that's all I've seen.

Mariner 9's camera had one severe design limitation that made quantitative decalibration of the images very difficult <The Mariner 69 cameras had the same problem>. Each vidicon image exposure was erased with repeat scans of an electron beam after electron beam readout from the camera, but the erasure was incomplete. Ghosts of previous images with some 5 to 10% of the brighness of the previous image, then fading slowly, persisted in subsequent images. In mapping strips of images, that wasn't terrible, but when the ghost images contained the bright limb of the planet, they were awful. The strength of each ghost depended on the pixel location, and the brightness of the previous image and the brightness of the current image. The resulting images were significantly degraded cosmetically and scientifically by the residual images.

Mariner Venus/Mercury 1973 (Mariner 10) solved the problem with perfect brute force engineering. Each of the twin cameras contained a ring of several small "wheat bulb" light bulbs! After each exposure was read out, the light bulbs INSIDE the camera were turned on, totally and uniformally saturating the vidicon surface with light. The cameras then erased the vidicon repeatedly, before taking a new exposure. Residual image was reduced to essentially undetectible levels.

The Viking Orbiters and Voyagers did the same thing. The "Light Flood" could be turned off when desired, as it left a background level of "glow" noise in the images, and when Voyagers, in particular, were doing long exposure low-light-level imaging, the light flood was "off".
tedstryk
The reason so much of Mariner 6/7 imagery was sent back in a lossy way or in analogue was the extremely limited storage capacity. Mariner 9's storage capacity wasn't too much better, but since it wasn't a flyby, it didn't need to take and store so many images in a hurry.
As for Pioneer, what I fear is that the data suffered the fate of the original surveyor data. The surveyor data was preserved in the form of photographic prints, not original transmissions - at the time, afterall, who stored images in an electronic format? I also wonder about the fate of the Pioneer Venus Orbiter Cloud Photopolarimeter dataset. It must be recorded somewhere. But how in the world to convert it into a useable format...
I had not realized the entire set of Mariner 4 matrices were available. That would be a neat project. But a boring one at first.
Bob Shaw
Somewhere in my box of space slides from the 1970s (produced by the UK Woodmansterne company) there's a colour far encounter image from Mariner 6 or 7. It shows, as I recall, half the planet and in about three-quarter phase. My dim memory also suggests that the image appeared in print, possibly in a National Geographic Magazine around 1970.

The colour was none to clever, and without doubt could be improved on these days!
tedstryk
QUOTE (Bob Shaw @ Apr 23 2005, 12:37 PM)
Somewhere in my box of space slides from the 1970s (produced by the UK Woodmansterne company) there's a colour far encounter image from Mariner 6 or 7. It shows, as I recall, half the planet and in about three-quarter phase.  My dim memory also suggests that the image appeared in print, possibly in a National Geographic Magazine around 1970.

The colour was none to clever, and without doubt could be improved on these days!
*


Here is that image.
deglr6328
blink.gif I am so consistently dumbfounded at the amazing depth and breadth of information posted by users here I just don't know what to say. Well done gentlemen. I really hope consideration is given by the creator of these boards to long term preservation of the discussions here.
edstrick
To chase down the history and existance of the Pioneer Jupiter and Saturn image data (and the lower resolution polarimetry images), basically somebody needs to systematically contact and query the original instrument team members *and* their grad students. Work on the polarimetry data continued longer <I think> than the images, through much of the 80's.

The Pioneer Venus data continued to be taken at times up maybe to the end of the mission, in the early 90's, and is much more likely to be intact <readibility of old tapes is a *real* problem>. Again, the science team members and their grad students are ones to contact.
Bob Shaw
Yup, that's the chappie!

And my memory is better than I thought - it's exactly as I dcescribed it!

Now, where *did* I put that dratted bus pass...
tedstryk
QUOTE (edstrick @ Apr 23 2005, 08:28 PM)
To chase down the history and existance of the Pioneer Jupiter and Saturn image data  (and the lower resolution polarimetry images), basically somebody needs to systematically contact and query the original instrument team members *and* their grad students.  Work on the polarimetry data continued longer <I think> than the images, through much of the 80's. 

The Pioneer Venus data continued to be taken at times up maybe to the end of the mission, in the early 90's, and is much more likely to be intact <readibility of old tapes is a *real* problem>.  Again, the science team members and their grad students are ones to contact.
*


Actually, after digging a bit, I need to amend my earlier comment. The NSSDC has the PVO cloud photopolarimeter digital dataset. They also have the digitial data for the Pioneer IPP at Saturn. That just leaves the Pioneer 10/11 datasets from Jupiter.
peter59
QUOTE (edstrick @ Apr 23 2005, 09:50 AM)
Mariner 6 and 7 returned two "primary" image datasets of Mars. Far Encounter and Near Encounter.  Far encounter data was narrow angle only, near encounter was alternating wide and narrow angle images.  The narrow angle camera was monochrome, with <I think> a yellow filter to "cut haze", while the wide angle camera had a 4 position filter wheel.  I think red/green/blue/green.

The spacecraft had dual tape recorders, derived from the Mariner 4 hardware.  Unfortunately, it did *NOT* have the capability to recorde the entire dataset in digital form.

All data was recorded on an *ANALOG* tape at full resolution, after being sharpened with a circuit that enhanced fine details.  Near encounter analog data was recorded after being passed through an automatic gain control filter <which totally trashed absolute intensity values for the data>.  Unfortunately, the taped data was degraded by significant in-flight buildup of tape oxide on the playback <record/playback?> heads, resulting in horizontal streaky noise and banding and occassional analog dropouts in the images.

Every seventh pixel was recorded on the DIGITAL tape recorder without automatic gain control, after having the two most significant bits chopped off, which badly "contoured" the digital data.  To make matters worse, the middle 1/4 or 1/5 of each image's digital data  was not recorded, spectrometer data being transmitted during that gap <and between the end and beginning of each scan line as well>.  BUT..... every 4'th digital pixel in the center gap was trasmitted in real time!....

The efforts to reconstruct the images were described in the Mariner 69 special report issue of the Journal of Geophysical Research, published in 1970 or early 71.  They were largely successful, producing 2 versions.  One was from the analog data, and was a "Maximum Discriminability" version of the data, best showing fine details.  The other was radiometrically decalibrated using preflight and some inflight data on camera background and shading and spectral response, starting from the reconstructed final images.  These show the real contrasts of the martian surface better, and the regional shading of the albedo markings.

The wide angle images were taken in overlapping swaths through alternating color filters, and some color information is clearly present in the images.  The viewing geometry changed from frame to frame as the field of view was something like 15 degrees.  I have never seen attempts to generate color images using the overlapping wide angle close encounter images.

Mariner 69 also returned a "secondary" image dataset... the every 7'th pixel data <missing that central stripe> was transmitted in real time.  Most of the far encounter data includes at most slivers of the planet's limb, as the disk was within the central stripe, but Mariner 7 transmitted a unique set of WIDE ANGLE "Late Far Encounter" data with the filter wheel stepping.  This data was not recorded for playback.  There is a picture floating around made from this data of a half mars <cut off by that central stripe> of the Sinus Meridiani area, in color, with mabye twice or so the resolution of most any earthbased mars imagery from that period.
*


Available Mariner 6/7 images at NSSDC:

1) ETE pictures (every 28-th pixel)
2) DV digital video pictures (every 7-th pixel)
3) CAV composite analog video pictures
4) Images reconstructed by JPL/IPL from the three data streams (CAV, DV, ETE) (partly and fully processed).
5) Images in orthographic projection processed by JPL/IPL in 1969.

Examples:

Images in orthographic projection:
Orthographic projection 1
Orthographic projection 2

DV digital video pictures (every 7-th pixel) from near and far encounter (with central gap).
Near encounter

Far encounter


All images are viewable by my software written for this Mariner 6/7 particular dataset. Software for Mariner 6/7 dataset
TheChemist
peter59,
thanks for providing the link to your wonderful site. What an amazing work you have done ! smile.gif
edstrick
One annoying problem with the radiometrically corrected Mariner 69 images was a "cleanup" that was only partially done. The camera had electrical interference that made noticible periodic noise "herringbone", etc. patterns in the data. This was removed from the full resolution analog data by Fourier transformation of the data, isolation of the noise frequencies in 2-D frequency space, and transformation back into Cartesian image space.

This was ***NOT*** trivial in 1970. Unfortunately, the same noise pattern was present in the 1/7 and the 1/28 digital data streams, aliased by the 1/7 and 1/28 undersampling of the data. You can see it in the pictures posted above. Unfortunately, they did not remove the periodic noise from the digital data streams, and that was put back into the images when the digital data was merged with the analog data. The radiometrically restored images thus had the periodic noise from the 1/7 data in the outer parts of the image, and the different pattern of noise from the 1/28 data in the middle strip. *SIGH*.

Easy enough to fix now, just very "fiddly" work. I really do want to see what color information we can get out of the Mariner 6 and 7 pics. I've wanted that for 35 years.
4th rock from the sun
QUOTE
...

Note that the mariner 4 images were taken in alternating red and green filters, with every third image not recorded.  So the pictures are: green, red, missing, red, green, missing, green, red, missing etc.  The corner of one image of each red/green pair OVERLAPPED by about 100 pixels, so there is some color data from the Mariner 4 images. 

....


With this information I processed the scanned Mariner 4 images avaliable here http://nssdc.gsfc.nasa.gov/imgcat/html/mis...er_4_page1.html
using the gray scale bars to "normalize" the images and resampling them to 200x200 pixels. Then I made mosaics from the image pairs and put them in a map by matching the visible surface features.
I also used the overlaping Red / Green areas to generate a small color area inside the mosaics.

I'm ataching a map with all the images and a mosaic. All this will be avaliable in my page soon! Click to view attachmentClick to view attachment
GregM
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edstrick
GregM and 4'th Rock are certainly on the right track. Both results, even if "quick and dirty" look quite decent The registration on the mariner 69 stuff is better than I expected. The "less red" color of Sinus Meridiani is certainly real.

Note that the Mariner 69 pictures exist in multiple versions. And both mission slewed the scan-platforms back to partially overlap the earlier imagery at a different phase angle. Mariner 7 also photographed overlapping coverage with Mariner 6 for comparison purposes.

Residual image of the martian limb is visible in the Mariner 7 color version. Subtraction of an earlier limb image, or a shifted version of one image from itself should substantially reduce the @#$@# ghost of the limb.

The best possible Mariner 4 work will be when somebody can scan and OCR the paper copies of the 6 bit pixel data lists "picture element matrices" in that Mariner 4 project final report volume. One of the more sophisticated, modern pixel interpolation techniques <not just bilinear or cubic convolution> image resampling would also help suck the most possible from the 200 x 200 images. The ultimate restoration of the Mariner 4 data would require some form of interpolation of the "contour lines" formed by the 6-bit digitization to synthetize pseudo-8-bit data.

Nice work... keep at it!.
tedstryk
Speaking of historical images, this is some work I did with some more recent historical images. It shows Europa and the Jovian rings. It is a mosaic of framelets from Galileo's C10 orbit. Europa appears multiple times within the sequence, but I edited that out. This shot gives you an idea of some of the Cassini-like shots Galileo might have send back had it not been sent across the country twice in a semi truck.

Phil Stooke
It's show and tell time.. I guess. Here's another new version of some historic images...

Click to view attachment

It's a polar projection of one of the Apollo 17 Station 6 panoramas taken at Split Rock on the slope of North Massif. The astronaut is at the center, standing on the rim of a small crater west of the rock. The rover and the other astronaut (Schmitt, I think, I don't have my notes with me) are downhill from the center of the scene. The reprojection exaggerates horizon topography in a rather bizarre way, but this is really intended for mapping in the vicinity of the science station.

Phil
Bjorn Jonsson
This is extremely impressive, IMHO especially peter59's work with the Mariner 6 & 7 images.

I have also been processing some old images, mainly from the Voyagers:

http://www.mmedia.is/bjj/images/

I have more that I'll put online someday. I have also scanned all Pioneer 10 & 11 images I could find. Many of these I have not seen online. I will probably add these to my website one day but I would just love to have these in digital form instead of scanned. Modern computers and software can do miracles, what I've seen here is much better than NASA's processing a few decades (!) ago.

I also recently downloaded all of the Mariner 10 images and have been playing with them. BTW are the earlier Mariner (4, 6 and 7) imaging datasets not available online - only on CDs ?
tedstryk
QUOTE (Bjorn Jonsson @ May 12 2005, 10:57 PM)
This is extremely impressive, IMHO especially peter59's work with the Mariner 6 & 7 images.

I have also been processing some old images, mainly from the Voyagers:

http://www.mmedia.is/bjj/images/

I have more that I'll put online someday. I have also scanned all Pioneer 10 & 11 images I could find. Many of these I have not seen online. I will probably add these to my website one day but I would just love to have these in digital form instead of scanned. Modern computers and software can do miracles, what I've seen here is much better than NASA's processing a few decades (!) ago.

I also recently downloaded all of the Mariner 10 images and have been playing with them. BTW are the earlier Mariner (4, 6 and 7) imaging datasets not available online - only on CDs ?
*


I have two projects of my own underway. First, I have some Surveyor 7 stuff that I am scanning that I intend to process. Secondly, I have some digital data for two or three Pioneer images from Saturn (I say two or three because there is one shot that may be a fragment of one of the other two - I need to check carefully). The problem is that it is in paper form, so this will take a lot of work.
GregM
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dvandorn
QUOTE (GregM @ May 16 2005, 10:27 PM)
<snip> I have always felt that Pioneer 10 & 11 never has recieved the attention or accolades that they deserved. The first spacecraft to Jupiter and Saturn for heaven's sakes! Part of the reason for that was that the imaging was very tricky, and never really processed very well compared with what could be done with today's technology.
*

The problem was more that the imagery was crude and nearly an afterthought -- it was crude by the standards of the time in which it was built.

The Pioneers were limited in that they were primarily fields-and-particles sensors. The magnetometers, especially, worked a lot better on a spinning spacecraft. And it's really tricky to develop a stationary, pointable scan platform on a spinning spacecraft. The Voyagers managed it, but they're bigger, better spacecraft than the earlier Pioneers.

So, since it was just cost- and weight-prohibitive to equip Pioneer with a stationary scan platform, the best they could do to provide imagery was to place a photometer on it and have the Pioneer's own spin scan the photometer through its field of view, one line per rev. The photometer was "nodded" on each scan to get an adjacent line.

That kind of imaging is rather inherently crude and low-resolution. It needed an awful lot of correction, because of precession of the spacecraft spin and the distance the spacecraft traveled relative to its target during the time it took to build up a single image.

But it was a HECK of a lot better than nothing!

-the other Doug
Phil Stooke
I promised earlier that I would post something from Surveyor 7 - and now I have to as I see Ted is about to trump me! So here are two images from Surveyor 7:

s7a.jpg is a detail, half the original resolution of my full pan but very heavily jpegged to make it small enough to post.

s7b.jpg is the full pan, reduced enormously in size. The full pan is about 10,500 pixels wide.

These were made by scanning ten prints of mosaic sections, joining them and removing the frame to frame tonal variations and other defects. Incredibly, in some areas it was even possible to correct mosaicking errors in the originals.

I have also made true full-resolution pans of a small area by scanning individual frames and mosaicking by hand. I will post something from that another time.

Phil

Click to view attachment

Click to view attachment
JRehling
QUOTE (GregM @ May 16 2005, 08:27 PM)
That's awsome. I have always felt that Pioneer 10 & 11 never has recieved the attention or accolades that they deserved. The first spacecraft to Jupiter and Saturn for heaven's sakes! Part of the reason for that was that the imaging was very tricky, and never really processed very well compared with what could be done with today's technology.  Voyager, Galileo, and Cassini came along and suddenly everyone forgot the Pioneers, but there is something very special to being the first.  If cameras existed 500 years ago, everyone would be interested in Columbus' landfall images, not nearso Vespucis'. Why should this be any different?
*


Well, Jupiter and Saturn didn't change much between 1972 and 1981, so the subject matter is absolutely fixed in the spacecraft case. You might consider Voyager to be showing you precisely the Pioneer view, only clearer!
But that said, Pioneer passed way below Jupiter's orbital plane, which makes those images unique, and Pioneer 11 I remember fondly for the quirk that it returned images of the shady side of Saturn's rings, making the B ring appear dark, and giving the whole shot a feeling of newness quite different than Earth-based photos of Saturn. It made me nostalgic for Pioneer 11 when Cassini returned its first pictures of the shady side of the rings, with that same profile of a bright A, dark B, bright C.
BruceMoomaw
If I remember correctly, Voyager 2 also got some backside shots of Saturn's rings. Nor must we forget that one remarkable close-in shot Pioneer 11 got which, by pure luck, simultaneously revealed the existence of the F Ring and confirmed the existence of a 10th moon of Saturn (since both Janus and what would later be named Epimetheus were only suspected, not confirmed, in the photos taken of Saturn when its rings were edge-on in 1966). As an added stroke of pure chance, Pioneer then flew within only a few thousand km of Epimetheus (I don't know precisely how close) -- close enough for its radiation detectors to clearly sense the wake that the moon was plowing in Saturn's radiation belts. As I recall, it was the timing of this event which enabled them later to determine that it was also Epimetheus, not Janus, that had turned up in the image.

Both moons' existence was confirmed just a few months later by ground-based photos during the planet's next period of edge-on ring views -- which finally cleared up the long-lasting annoying question of Saturn's possible 10th and 11th moons by revealing that Janus' orbit had been miscalculated by Dollfus in 1966 and that it was (to astronomers' amazement) co-orbital with Epimetheus. The same photos revealed another major surprise: Helene, the first Lagrange moon discovered in the Solar System.

As for Pioneer's still-unmatched overhead shots of Jupiter's polar regions: the Juno orbiter, if it's selected for New Frontiers, will include a camera for views of Jovian polar weather patterns -- although its PI tells me that it's as much for PR as for real science.
tedstryk
Phil, I am nowhere near trumping you. It will be a month before I have anything to show, and my project is much less ambitious - just to clean up a few frames. As for the Pioneer data, it should be added that the scans were only 6-bit.
Bob Shaw
Phil:

Very, very nice!

Now, the $64,000 question (probably easily answered with someone with an eye for sun angles and knowledge of the landing point): Which way are we pointing?

And are the rim mountains of Tycho (or any other large crater) visible, or what?
dvandorn
QUOTE (Phil Stooke @ May 17 2005, 08:26 AM)
I promised earlier that I would post something from Surveyor 7 - and now I have to as I see Ted is about to trump me!  So here are two images from Surveyor 7:

s7a.jpg is a detail, half the original resolution of my full pan but very heavily jpegged to make it small enough to post. 

s7b.jpg is the full pan, reduced enormously in size.  The full pan is about 10,500 pixels wide.

These were made by scanning ten prints of mosaic sections, joining them and removing the frame to frame tonal variations and other defects.  Incredibly, in some areas it was even possible to correct mosaicking errors in the originals.

I have also made true full-resolution pans of a small area by scanning individual frames and mosaicking by hand.  I will post something from that another time.

Phil

Click to view attachment

Click to view attachment
*

Phil, is there anywhere you can post the full-resolution images (even temporarily) where we can link to them? I would *really* like to see them at full resolution... *smile*...

-the other Doug
dvandorn
QUOTE (Bob Shaw @ May 17 2005, 02:39 PM)
Phil:

Very, very nice!

Now, the $64,000 question (probably easily answered with someone with an eye for sun angles and knowledge of the landing point): Which way are we pointing?

And are the rim mountains of Tycho (or any other large crater) visible, or what?
*


The following comes from my recollection of the supporting text in the NASA publication "Exploring Space with a Camera," where the landing point and orientation of the lander were discussed in detail.

The "mountain range" visible at the horizon in Phil's first image *may* be the northeast rim of Tycho. It may also be the ejecta ridges concentric to the rim.

Surveyor VII landed about 40 km northeast of the main rim. The topography is *still* poorly-enough understood that it's not clear whether or not the ridges of ejecta would break its line-of-sight to the uplifted rim. But the mountains visible on the horizon are in the right direction to be the actual rim -- if the rim sticks up high enough to be visible from 40 km away.

-the other Doug
Phil Stooke
The detail looks west and north, and the full pan has north roughly at the center and south at each end. The whole area is 30 km north of the rim crest of Tycho, in rolling topography, so you never see too far. Prominent hills north of the spacecraft, seen in these views, extend along a ridge from about 5 km away to 20 km maximum at the north point on the horizon (just a little hilltop among lots of others). So all these hills are on the Tycho ejecta blanket and no discrete large crater rims are visible.

The full size datasets will eventually end up on the Photojournal (current plan). Until then and the publication of my book I will not be making them public. (Though Ted has some!)


Phil
Bob Shaw
Thanks, guys!
tedstryk
QUOTE (Phil Stooke @ May 17 2005, 08:05 PM)
The detail looks west and north, and the full pan has north roughly at the center and south at each end.  The whole area is 30 km north of the rim crest of Tycho, in rolling topography, so you never see too far.  Prominent hills north of the spacecraft, seen in these views,  extend along a ridge from about 5 km away to 20 km maximum at the north point on the horizon (just a little hilltop among lots of others).  So all these hills are on the Tycho ejecta blanket and no discrete large crater rims are visible.

The full size datasets will eventually end up on the Photojournal (current plan).  Until then and the publication of my book I will not be making them public.  (Though Ted has some!)


Phil
*


I could share them, but Phil would have to kill me biggrin.gif
Phil Stooke
I am attaching a set of maps which portray the Surveyor 7 location all the way from regional scales to the immediate vicinity of the lander. They are considerably reduced in size and quality from the originals to make them postable. This "zooming in" method of portraying a site is what I am doing for every mission.to the Moon... and later Mars.

The Tycho rim is 30 km south of the lander, but the size of boulders on the southern horizon makes it very clear that the horizon in that direction is VERY close... only tens of meters away. There is no chance the rim crest of Tycho is visible. You can't rely on the older reports.

Incidentally, similar kinds of arguments show that the position usually mapped as the Luna 9 landing site can't be correct either. I move it at least 20 km NNE of its usual mapped site, on very strong evidence from the surface images themselves.

Phil

Click to view attachment

Click to view attachment

Click to view attachment

Click to view attachment
chris
Very nice, Phil.

Chris
Bob Shaw
Fascinating!
tedstryk
QUOTE (Bob Shaw @ May 18 2005, 08:43 PM)
Fascinating!
*


Does anyone know a good program for manually entering numerical values from a paper copy to make an image file? I could do it in Photoshop, but it would take forever and a day.
Bjorn Jonsson
QUOTE (tedstryk @ May 22 2005, 07:49 PM)
Does anyone know a good program for manually entering numerical values from a paper copy to make an image file?  I could do it in Photoshop, but it would take forever and a day.

If you have these numbers in a simple text file I can easily convert the file to a PNG (and if this because of the Pioneer images mentioned earlier in the thread then this is something I myself am interested in).
tedstryk
[quote=Bjorn Jonsson,May 22 2005, 11:23 PM]
[quote=tedstryk,May 22 2005, 07:49 PM]Does anyone know a good program for manually entering numerical values from a paper copy to make an image file? I could do it in Photoshop, but it would take forever and a day.[/quote]
If you have these numbers in a simple text file I can easily convert the file to a PNG (and if this because of the Pioneer images mentioned earlier in the thread then this is something I myself am interested in).
*

[/quote

I can work on entering them...unfortunately, the old 1970s typewriter that wrote the document was of such poor quality that I will have to enter the numbers manually, but I will e-mail you the files when I get done.
GregM
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