Mariner 6 and 7 Mosaics Options

[tedstryk]

Mariner 6 Mosaics.

I have reprocessed the mosaics from Mariner-6. I reconstructed the frames based on both the analog and the digital transmissions of the image. The analog images were filtered to enhance the visibility of topography, wiping out brightness information. The digital images were in 7-bit form and only a fraction of the pixels were transmitted, but they contain proper brightness information. A set of images combining the two was constructed at the time, but there is definitely some loss of detail. Working in 16 bit, I can do a better job. I also worked to remove after-images. Another problem is that the wide angle camera that took these mosaics cycled through filters but did not take the images on top of each other for color combination. Rather, the filters were simply included to test the photographic properties for color studies on future missions (although Mariner-7 did some color work). As a result, I had to modify the mosaics so that the frames would cosmetically match.

Far encounter (last two frames).



Mosaic 1



Mosaic 2 and 3. These overlapped. Also, there was a small gore between the two mosaics. I filled it in with Mariner 7 near encounter data.



Narrow angle. Narrow angle frames 6 and 14 happened to slightly overlap, allowing the one narrow angle mosaic to be made.



I am now working on Mariner 7 mosaics. There are more Mariner 7 images, and due to some issues with the digital versions of them, they are proving quite difficult. I hope to post them soon.
I also hope to further clean up the Mariner 6 frames and mosaics.

[mcaplinger]

The digital images were in 7-bit form and only a fraction of the pixels were transmitted...

Sorry to resurrect this thread, but it was linked in Emily's blog posting on Bruce Murray and early Mariner images, see http://www.planetary.org/blogs/emily-lakda...ner-images.html

The statement about only a fraction of the pixels being transmitted is not completely accurate: see http://mars.jpl.nasa.gov/mgs/msss/camera/i..._2_00_vishniac/ and http://mars.jpl.nasa.gov/mgs/msss/camera/i...m7_imaging.html for a description of how the MM69 camera system worked. All of the pixels were transmitted, but some only in analog AC form.

As for "Murray's stubborn insistence that it would be ludicrous to send a spacecraft to Mars and not include a camera", NASA is of course just about to do that with MAVEN. The PI even speaks with pride (see http://www.aviationweek.com/Article.aspx?i...759.xml&p=2 ) about his resistance to "science creep", even though AFAIK the mission cost a fairly large fraction of the total cost of MRO -- $671M for MAVEN, $720M for MRO.

Disclaimer: being a camera designer I obviously have some bias.

[tedstryk]

For the color approach sequence, there was no analog transmission. Just the limited digital data. The tape recorder was being saved for near encounter.