[X] My Assistant

[MizarKey]

Thanks to Ustrax in this post , 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


Larger

February 26 program 5 image 12Z


Larger

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...

[4th rock from th...]

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!

[ngunn]

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

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

[babakm]

I find Google Mars pretty useful for these kind of questions. Using this page from Don Mitchell's site, a bit of location guidance 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.

Attached thumbnail(s)

 

[4th rock from th...]

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.

[4th rock from th...]

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

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

[tedstryk]

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:

[djellison]

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

[babakm]

Here's my version of the photos and mosaic, based on the location finding work above.

That what I meant to do Very nice.

Looks like that orbit was on a pretty cloudy day.

[dvandorn]

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

[Dio]

>> 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...

[Guest_Myran_*]

djellison wrote: The reason they used to use film developed on board is because that was the only means they had to store images rapidly enough.

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.

[Dio]

LO images with typical damages:

http://www.lpi.usra.edu/resources/lunar_or...g/iv_085_h3.jpg
http://www.lpi.usra.edu/resources/lunar_or...g/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.

[Phil Stooke]

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

[tty]

LO images with typical damages:

http://www.lpi.usra.edu/resources/lunar_or...g/iv_085_h3.jpg
http://www.lpi.usra.edu/resources/lunar_or...g/iv_103_h1.jpg

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.

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