[X] My Assistant

[stewjack]

Now that we know where we are going, I thought we could use a topic about our future route. I hope that a few images will get the rover rolling - downhill.

READY START

BACKGROUND
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From Steve Squyres Misson Update
Octoberber 4, 2005

Extending eastward from the summit of Husband Hill is a broad ridge that we've named Haskin Ridge. It trends ENE from the summit, does a little dog-leg to the right, and then trends ESE for a bit. Right at the dog-leg there's a pretty steep step, which we're not certain we can get down. So we're going to descend the upper portion of the ridge, right to where the step is, and assess the situation. If we can see a safe route, then we'll continue down onto the lower portion of Haskin Ridge.
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My Image of Haskin Ridge
I tried to get the best image of Haskin ridge that was available, and this is a crop from a true color TIFF summit panorama, located on the the Cornell Pancam web site. I converted the tif file to a gif file to save some download time.

Warning : File Size : 1.7 MB
Cornell True Color Pan of Haskin Ridge

Reference
WEB page of Husband Hill Summit Panorama
Warning: File Size : 80 MB !!!!
Preliminary Spirit Pancam of "Husband Hill Summit" Panorama

Jack

PS If you can't see the "steep step" that Squyres mentions - try this orbital image. I believe that the "steep step" is the dark shadow cutting across the ridge that is located directly under the word CRATER. I think that it is also visible in the true color pancam image, but it is less obvious.

Orbital View of Husband Hill and Basin

[jvandriel]

A panoramic view of part of the rocky road ahead down to the Innerbasin.

A panoramic view taken on Sol 625 with the L7 pancam.

Look at the angle of the images.

jvandriel

Attached thumbnail(s)

 

[dilo]

Sol621: the destination way in a 12 PanCam pictures stitch (more images are coming!):

Attached thumbnail(s)

 

[stewjack]

Sol621: the destination way in a 12 PanCam pictures stitch (more images are coming!):

Fantastic color panorama dilo! If there are any visible seams in that graphic - I didn't see them.

With your permission I will keep that image on my hard drive. It should be useful for long baseline stereo, as we drop down toward the basin.

Disregarding time and resources, IMHO we can never get to many images. No one image has the complete truth.

For me, the MOC orbital images of are often difficult to correlate with the "ground truth" images. I created a long baseline animated gif of the NE basin, and then I spent hours trying to relate what I saw in the flicker, with what I saw in the MOC image.

I did much of the work for my own curiosity, but in case anyone is interested, I will post my material here. Anyone trying this should probably have all three images open in browser windows for simplfied comparisons.

Comparison of Orbital and "Ground Truth" Imagery for NE Basin

1st: Image Overview of Basin File size 365 kB

I added some green lines to this image to draw your attention to some ridge-like features that are visible in all three images. The green lines are offset, and run parallel to the ridge features. The green lines do not cover the ridge features.

MOC-OverviewBasin-with-lines.gif


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2nd: SOL605 NAVCAM Crop of NE-Basin File size 344 kB

I also added some green lines to this image to draw your attention to the ridge-like features that are visible in all three images. These green lines are also offset, and run parallel to the ridge features. The green lines do not cover the ridge features.

605-NAV-crop-NE-Basin-with-lines.gif


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3rd: Animated GIF of NE Basin File size 571 kB

582-605-NAV-Crop-NE-Basin-flicker.gif


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I really like this animated gif. I managed to achieve some 3D effects with Ramon Hill, at a distance of about a kilometer.

You should not consider my flicker gif's to be scientifically accurate. The separation of long baseline images is unknown, and I don't pretend to understand what I am doing when I register the images. Since I don't fully understand the process, I can only act on the results.

Jack

[dilo]

Nice job, stewjack (I'm happy you like my panorama!).
About your patient identification work, baseline between Sol605 and 621 should be close to 25m (based on last route map) and is roughly perpendicular to the line of sight of these images (best parallax condition)...

[stewjack]

Nice job, stewjack (I'm happy you like my panorama!).
About your patient identification work, baseline between Sol605 and 621 should be close to 25m (based on last route map) and is roughly perpendicular to the line of sight of these images (best parallax condition)... 

25 meters is "terrain eyes," while the 30 centimeters, that I have heard is the separation between the L & R navcams, are only "rock eyes."

The only strong conclusion of my "identification work," is that orbital imaging should be used with caution. Particularly by amateurs such as myself. There are many apparent similarities, but also some apparent differences.

I am changing the subject slightly, but not completely, because this terrain feature was the first one that I noticed was not visible in orbital images.

I have some imagery of terrain, just outside of the western rim of the basin. I was planning on working with that terrain, before I learned that spirit is taking the eastern route down the hill. Those image files are now going into storage, but I don't know what to call that terrain. My memory suggests "rough" or "etched" terrain. If you, or anyone reading this, knows what I am talking about, and knows a standard name, I can label my graphic files usefully. The terrain has a "frothy" or "choppy" appearance to my eye. I know that this terrain was mentioned more than once by Steve Squyres, but I can't locate it in his mission updates, and I can't search for more information without a name!

Jack

[Tesheiner]

The only strong conclusion of my "identification work," is that orbital imaging should be used with caution.

Agree with you, and would like to remind everybody about another point.

MOC imagery that has been used here is in some cases NOT map-projected. Simply crops of the same pictures E03-00012 and/or R02-00357 available from e.g. MSSS website.
The scale of those images is not the same in the x and in the y axis (the aspect ratio is not 1) so any distance and/or heading measurements based on them without taking into account such ratio would be bogus.

For instance, this image (R02-00357) has a resolution of 2.98 m/pix on the x axis but also a pixel aspect ratio of 1.5, meaning that the resolution on the y axis is 4.47 m/pix.

Edited: Here below is a portion of that picture, covering Columbia Hills. The first image is a simple 1024x1024 crop of the MOC picture, while the second was corrected to have the same resolution on both axis.

[stewjack]

Agree with you, and would like to remind everybody about another point.

MOC imagery that has been used here is in some cases NOT map-projected. Simply crops of the same pictures E03-00012 and/or R02-00357 available from e.g. MSSS website.
The scale of those images is not the same in the x and in the y axis (the aspect ratio is not 1) so any distance and/or heading measurements based on them without taking into account such ratio would be bogus.

WOW! And I thought I was being cautious when I used an official JPL image - with a meter bar!

Actually, I wouldn't be surprised if the meter-bar was accurate - but only for east - west measurements!



MOC-OverviewBasin-with-lines.gif

Jack

[Tesheiner]

WOW!  And I thought I was being cautious when I used an official JPL image - with a meter bar! 

...

MOC-OverviewBasin-with-lines.gif

Jack

Official JPL image?
Don't think so.