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Posted by: MizarKey Nov 2 2006, 09:44 PM

Thanks to Ustrax in http://www.unmannedspaceflight.com/index.php?showtopic=3183&st=315#, I've had a chance to see some of the Russian images I've never seen.

It looks like they had some problems with stitching or something. Note these two:

February 25 program 4 image 8Z


http://www.mentallandscape.com/C_Mars05_4_Z08.jpg

February 26 program 5 image 12Z


http://www.mentallandscape.com/C_Mars05_5_Z12.jpg

Same approx. area, one has a folded landscape on the left, the other has an old crater...right hand side appears to be the same though. I don't know if there's a way to find out where this area is to compare it to MOC images...

Posted by: 4th rock from the sun Nov 3 2006, 11:48 AM

I really haven't checked but I think that those images were taken by photo cameras and then scanned on the spacecraft and transmited. So all of the defects might be artefacts of film development.
The strange thing is flying a image scanner to Mars and use it on onboard film prints and not to image the planet itself!

Posted by: ngunn Nov 3 2006, 01:05 PM

Would it be that the scanning process was just too slow relative to spacecraft motion, whereas film gave an instantaneous image?

Posted by: babakm Nov 3 2006, 05:17 PM

I find http://www.google.com/mars/ pretty useful for these kind of questions. Using http://www.mentallandscape.com/C_CatalogMars.htm from Don Mitchell's site, a bit of http://nssdc.gsfc.nasa.gov/database/MasterCatalog?sc=1973-049A from NASA and Google Mars, it was relatively easy to find the context for that specific imaging run (Program 5). See the first attachment linked below for context. I've ROUGHLY dropped in the 11 Mars 5 images (5.Z is missing) into a visible light map (attachment 2) for reference.

Zooming into the specific area of image 12.Z (attachment 3), there is no sign of the mystery ridge, but there are plenty of other possible culprits: Clouds.

Posted by: 4th rock from the sun Nov 3 2006, 09:33 PM

Nice match! It does show the data in context. The Mars 5 photos are not that bad after all

Here's my version of the photos and mosaic, based on the location finding work above. It's a higher resolution version, because I processed the Mars 5 images to remove most of the noise and brightness variations and the deserved a bigger size.

Posted by: 4th rock from the sun Nov 3 2006, 09:39 PM

Makes sense but at least from a modern technology point of view it's a complicated solution.
Perhaps the main objective was to get high resolution photos of the planet. That might be impossible with a primitive digital camera (pointing problems, noise, bit resolution, etc). But the Pionners didn't even have a camera and got decent images of Jupiter

Posted by: tedstryk Nov 4 2006, 12:11 AM

That is some impressive image location!

I am fairly sure that the differences between the images that started this thread are film defects. They occur in several Mars-5 images, and in som cases are more glaringly obvious, such as in these:

http://img171.imageshack.us/my.php?image=mars5exam1.jpg

Posted by: djellison Nov 4 2006, 12:19 AM

The reason they used to use film developed on board is because that was the only means they had to store images rapidly enough. Take the photo, store it as film, and then you can spend the next few weeks scanning them in a fax like fashion to send them home at a rate the spacecraft can manage.

I think...
Doug

Posted by: babakm Nov 4 2006, 02:35 AM

That what I meant to do Very nice.

Looks like that orbit was on a pretty cloudy day.

Posted by: dvandorn Nov 4 2006, 04:49 AM

Also recall that the Lunar Orbiter series worked in a similar fashion to the Mars-5 system, taking pictures onto photographic film and scanning the film with a photomultiplier system for read-out and transmission. That system resulted in very high resolution images of the Moon, but had an inherent issue with the seams between the readout lines.

-the other Doug

Posted by: Dio Nov 4 2006, 09:40 PM

>> Same approx. area, one has a folded landscape on the left, the other has an old crater...right hand side
>> appears to be the same though.

Typical film damage.

>> The strange thing is flying a image scanner to Mars and use it on onboard film prints and not
>> to image the planet itself!

There obviously should be intermediate data storage onboard anyway, because of
(a) Scan speed is not equal to transmission speed
(b ) High-gain antenna of Mars probe was not pointed to Earth during reconnaissance session

At the moment there were no tape recorders with transverse registration (at least, no suitable for space use). So, the choose was between magnetic tape and photographic film. Films provided the maximal possible information density.

>> Would it be that the scanning process was just too slow relative to spacecraft motion, whereas
>> film gave an instantaneous image?

>>> Perhaps the main objective was to get high resolution photos of the planet. That might be impossible
>>> with a primitive digital camera (pointing problems, noise, bit resolution, etc). But the Pionners didn't
>>> even have a camera and got decent images of Jupiter

"Mars" also had two scanning camera onboard. But yes, of significantly less resolution (3 km/pix instead of 0.05 to 1 km/pix for photo camera). Data from scanning cameras were stored in magnetic tape.

>> The reason they used to use film developed on board is because that was the only means they had to
>> store images rapidly enough. Take the photo, store it as film, and then you can spend the next few
>> weeks scanning them in a fax like fashion to send them home at a rate the spacecraft can manage.

At the moment film storage had the next advantages over the magnetic tape/videocon:

1) Allowed to use wide-angle objectives
2) Allowed more high shot rate
3) Previous two puncts results in possibility to accomplish stereo survey and color survey.
4) Lesser overall weight of videosystem
5) Lesser energy supply
6) Greater data density
7) Easily implemented preview mode and changed resolutions of scanning
8) No necessity to clean out memory during survey.

>> Also recall that the Lunar Orbiter series worked in a similar fashion to the Mars-5 system

Though LO used dry reactives and Marses had not. Internals were essentially different.

Some LO images also have series of amusing atrefacts, recalling green men invasion. I will look for example...

sorry my english...

Posted by: Myran Nov 5 2006, 02:24 AM

Correct, it was one of the main reasons for using film. The alternative would have been one TV camera which back then was one electronic tube didnt have that much resolution and gave one noisy image. So film were the better alternative.

And storing information on tape was one technology that was quite immature. Many TV programs from back then was in fact preserved by putting one film camera on a special TV monitor, those had some other kind of phosporous than a regular monitor.

The main problem with the early Russian space program was however the lack of a counterpart to the DSN, they simply were unable to keep their radio dishes targeted on their probes for any longer period of time. And this was one reason they made their spaceprobes to run on automatic for quite some time without the need for human control.

(The paranoia of the soviet system or was that national pride might have stopped them from building any one elsewhere. This led to the coup when Jodrell Bank got the first images from the surface of the Moon among other things.)

Later on they had a few ships sailing the oceans to get better coverage. There were accusations that those ships were spyships listening in to the military radio communication of the western nations, perhaps they sometimes were serving that dual purpose.

Posted by: Dio Nov 5 2006, 08:49 AM

LO images with typical damages:

http://www.lpi.usra.edu/resources/lunar_orbiter/images/img/iv_085_h3.jpg
http://www.lpi.usra.edu/resources/lunar_orbiter/images/img/iv_103_h1.jpg

(obviously there is alien base in the Moon)

>> Later on they had a few ships sailing the oceans to get better coverage.

There were about dozen of such ships well before Mars-71. But they were incapable to relay with intreplanetary probes. They were intended to support manned missions and lunar probes.

>> The paranoia of the soviet system or was that national pride might have
>> stopped them from building any one elsewhere

Though soviet system had a number of amusing features, it is unfounded to put to its "paranoia" that the things absolutly impossible at the moment were not done. Where the "soviet world-wide system of dishes" should be located? In Cuba and Ephiopia? May be it would be still better USA to sell a small piece of DSN time to Soviet Union? Such a good neighbour relations.

>> The alternative would have been one TV camera which back then was one electronic tube didnt have that
>> much resolution and gave one noisy image.

It should be mentioned that this was not conseqence of soviet inability to create decent videocon cameras for space use. There were such cameras (Kosmos-144, manned program etc). Though USA had stronger positions in this technology, they principially had the same choose. One can compare videosystems of nearly simultaneous Mariner-9 and Marses-71, 73.

Posted by: Phil Stooke Nov 5 2006, 02:13 PM

Welcome to our discussion, Dio. It's good to have contributions from Russia. If you look back through this forum, under Venus, Moon and Mars, you will see we have a lot of interest in the Soviet missions. Of course there is still a lot more to learn. But I am especially interested in future developments including Phobos-Grunt and Luna-Glob.

Phil

Posted by: tty Nov 5 2006, 04:29 PM

Seems to me that one site in Cuba, one in Crimea and one near Vladivostok should work just as well as Goldstone-Madrid-Canberra except perhaps at high southern latitudes.

tty

Posted by: Dio Nov 6 2006, 11:15 PM

>> Welcome to our discussion, Dio. It's good to have contributions from Russia. If you look back through this >> forum, under Venus, Moon and Mars, you will see we have a lot of interest in the Soviet missions. Of course >> there is still a lot more to learn. But I am especially interested in future developments including
>> Phobos-Grunt and Luna-Glob.

Thank you, Phil.

I definilely heard from some person working in Lavochkin that Luna-Glob is entirely paper work and PR of authorities. No real work was accomplished in this area since middle 90th.

>> Seems to me that one site in Cuba, one in Crimea and one near Vladivostok should work just as well as
>> Goldstone-Madrid-Canberra except perhaps at high southern latitudes.

In retrospective view, Cuba could be nice place geographically, but politically troublesome.

Posted by: MizarKey Nov 10 2006, 07:30 PM

Many thanks to Babakm for his http://www.unmannedspaceflight.com/index.php?showtopic=3427&st=0# and 4thRock too. Now I'll go looking through MGS for closeups of the region.

I also appreciate everyone else who helped to explain the imaging on those early probes.

Dio, it really is great to hear from someone in Russia and I look forward to any image you can provide that aren't mainstream.

Posted by: JonClarke Nov 11 2006, 05:30 AM

In your opinion is this true of the Phobos Grunt mission also?

Thanks

Jon

Posted by: Dio Nov 12 2006, 07:44 PM

My words on this subject here are just the second-hand testimony, so my personal opinion is of no value.

The same source as above claimed that assembly of Phobos-Grunt craft is gradually carried out, though it is not work of high internal priority for Lavochkin and it was repeatedly stalled during last years. After multipe delays, re-plannings etc., noone could get qualified estimate of a-priory success ratio. There is lots of scepsis about this project. But the situation is different from Luna-Glob.

As I was informed, modern Lavochkin projects could be roughly devided to three parts.

First, alive ones with approximately clean perspective, include Spectr-R and Electro-L.

Second are half-alive, Phobos-Grunt and Spectr-UF among them.

3rd, "Luna-Glob", "Resonans" and "Spectr-M" were characterized as programs, existence of which "became known to Lavochkin collaborators from newspapers" and "to this list one could easily append landing on the surface of Sun and delivery of samples from Pluto".

Posted by: Phil Stooke Nov 12 2006, 09:24 PM

4th Rock said "The strange thing is flying a image scanner to Mars and use it on onboard film prints and not
to image the planet itself!"

Not the same kind of scanner! The film negatives were scanned using a narrow light beam, scanned across the film in a raster, measuring the attenuation of light by the varying opacity of the negative. That isn't the same as a scanning camera that could image Mars.

Phil

Posted by: 4th rock from the sun Nov 12 2006, 11:48 PM

Ok, I understand that, I was just thinking out loud about old technology and it's limitations. It was more of a "what if" question.

Here's a new Mars 5 mosaic, merging the previous results with wide angle images and color compositions. Data from the last 2 imaging sessions was used as base map for the high resolution images.

The image is big so that the highres images keep some quality.

Seen like this, I think that Mars 5 did get very good images ;-)

Posted by: nprev Nov 13 2006, 02:05 AM

Yes, really not at all bad...comparable to many Mariner 9 frames in your rendering, 4Rock. Man...sure wish the landers had made it!

Posted by: 4th rock from the sun Nov 13 2006, 12:12 PM

The problem with the Mars 5 (and 4) images is the lack of flat and "bias" field correction to the raw images. Once you use them, the surface details become visible and the images fit into very nice mosaics. I don't think that the computers of the time were able to perform this type of processing, or even if the theory was known at the time. That's why the images look so poor, they only show the limitations of the imaging system and not it's potential ;-)

Posted by: JonClarke Nov 13 2006, 08:36 PM

I would not be so deprecating of your contribution. It is most valued. Thanks for sharing it.

What you say is a bit disapointing, but understandable under the circumstances. It's good to hear that Spectr-R and Electro-L are looking good, and that the fact that some work is still being done Phobos-Grunt and Spectr-UF is encouraging. I hope they fly. I met some people from Lavochin several years ago, I was most impressed.

Best

Jon