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.

[Phil Stooke]

Very nice!

On my originals and on this projection of them you may notice faint streaks near the north pole which look like the fabled canals of Mars. They are canals... as portrayed on the old ACIC Mars Chart MEC-1 published in 1965. Some sources show an incorrect date of 1962, which is the date the material for the background drawing was collected.

For my first Mars book I prepared a chronological series of Mars global maps. The ACIC map was scanned and the names and grid removed digitally. The polar sections were shown as several orthographic drawings but by an immense amount of wizardry their polar sections were combined and reprojected to create the big cylindrical map which then became my two hemispheres.

Then it was time to add the Mariner images. Mariners 6 and 7 arrived when the south pole was illuminated and turned towards the spacecraft, so the north pole was not seen. I projected the far encounter images to make a global map up to about 60 north. The north polar area came from the previous map in the sequence. Only with Mariner 9 did that get replaced.

Phil

[Antdoghalo]

For the far encounter, I noticed you used only Mariner 7 in that but I noticed some areas particularly Malea Planum where 6 had better imagery so I used that there.