[X] My Assistant

[4th rock from th...]

Here are some reprocessed P11 images of Saturn. I've used parts of different images to complete the missing ring edges on some images.

The image for 1979-09-01 is a mosaic of several images obtained that day, and suffers from changes in the spacecraft viewing angle.

I've made an effort to colect all the images and information avaliable on the net, but not much is avaliable with correct dates and satellite identification and I might have got some things wrong

When I have the time, I'll post some more Pioneer reprocessed images

[edstrick]

The real problem with the Pioneer images at Saturn is that they don't show much. Data rates were low and dropping as Saturn was days from solar conjunction, so close-in pics were narrower than at Jupiter. Worse, light levels were much lower than at Jupiter and the Pioneer spin-scan camera couldn't take longer exposures, so the data's noisier. And Saturn is so much blander than Jupiter, almost no cloud features show other than the belts. What they show that's new is the high phase view and the unlit side of the rings, and that's about it.

[tedstryk]

Here is another mosaic. This one shows Mimas below the rings and its shadow above the rings.

[GregM]

.

[JRehling]

Very nice. It looks to be free of the geometric distortions from the spin-scan. Colour looks very "realistic" as well. I think that this is a definate improvement over the "old" P-11 Saturn images.

It really does look suddenly Voyagerish in quality.

Of course, like those audiophiles who claim to prefer vinyl, I have such nostalgia for Pioneer 11 that I *like* the grainy images. *grumble* *grumble*

Just kidding -- keep on truckin', Ted.

[tedstryk]

There are three reasons to collect and reprocess old planetary images. One is to pull out new scientific information and to create a baseline for studies of temporal phenomena. The other two are what most of us here are involved in.

One is what I spend most of my time on - compared to the billions of photographs from different time periods and places that we have of Earth, both from the ground and space, we have relatively few of other worlds - even Mars pales in comparison. We have earthbased telescopic views, but until webcams and adaptive optics came along, it was impossible to take a planetary picture that didn't look blury when reproduced at a decent size except with excellent equiptment on a rare night. Of the images we do have, we only tend to see a small selection, perhaps those pulled out of the pile for "instant science" during a flyby, or those selected for use in the post-mission articles in Science or Icarus. The Voyager and Viking missions, for example, captured a plethora of beautiful shots that rarely see the light of day. In addition, the views we see are often impacted by outdated processing techniques (which sometimes goes as far as mosaics made of prints glued or taped together) as well as generational loss from scans made from scans made from scans, etc. Then there is data that was not recorded and or stored in digital form, and that was taken by crude imaging systems. With the processing techniques available at the time, even if science data could be gleaned, pretty pictures were out of the question. With Pioneer 11, my goal is to get beyond the limits of the Imaging Photopolarimiter and create nice looking (if small) photographs showing what Saturn looked like in September 1979, or what Jupiter looked like in 1973 and 4.

However, that brings me to the third reason - the preservation of history. When images that I have processed, such as my Phobos-2 and Mars-3 work, as well as those of others (4th rock and Phil Stooke come to mind), we create far nicer views that the scientists were able to produce at the time of the mission. So even if I can make a Pioneer image look Voyager-ish in quality, while I might have created a better depiction of Saturn, it is no longer a record of what the scientists (as well as the public) were viewing at or around the time. Pre-Apollo, we didn't have views of the lunar surface as nice and unobstructed as Phil Stooke's panoramas - they were covered in mosaic lines and light and dark areas of the vidicon. Therefore, the earier versions of these images still hold great value - it is these images that show us our best view of neigboring worlds in the mid '60s (Surveyor) or 1979 (Pioneer). However, if we want an idea of what we might have seen standing near Tycho on the lunar surface or hurtling towards Saturn, the enhanced versions are better.

I share nostalgia for the old Surveyor, Mariner, Pioneer, Voyager, and Viking (I could make this list longer - you get the idea) - they were my initial tour of the solar system. Of course, I am not a techie - There is something organic about things that are not digital that I like.

[tedstryk]

Here is an approach sequence. The closest shot is actually a mosaic of the best images from close encounter.

Ted