photonovore
Moonatic
Reged: 12/24/04
Posts: 2792
Loc: tacoma wa
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In connection to some study of basin rings I noticed that MONS PENCK is shown on the VMA Altitude overlay as a *depression* and not as an elevated feature (It is a blue area surrounded by green--green is supposed to indicate a higher elevation than blue). I thought this must be a mistake but when I called up the Clementine LIDAR color topographic map from the USGS website I got the same result:
"Topographic data from the Clementine laser altimeter were combined with topographic data collected photogrammetrically from Clementine stereo images. The resulting topographic product was colored based on elevation value and combined with the shaded relief data to form the final photomosaic. Blues and greens are lower elevations, reds and yellows are higher." Below is the key for the Clementine LIDAR topo color maps:
Here's a CLA image of this area...depression?! How?
Chuck Woods gives a description: "Just west of Theophilus near the crater Kant (with its off-center central peak) is a rectangular block that sticks up like a hitch-hiker’s thumb. Formally known as Mons Penck, the thumb is nearly as high (4 km) as Theophilus is deep (4.4 km)."
So...what is going on I wonder?? How could a mountain peak of this size show up as a depressed area>?  Is there something amiss with the Clementine dataset or am I missing something in interpretation?
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Mardi
4" achromat, ETX-70, 8"cat.
Whitepeak Lunar Observatory Website
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revans
Carpal Tunnel
Reged: 09/26/05
Posts: 1637
Loc: Fitchburg, MA
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Mardi,
If you send me a copy of the image without writing or arrows on it and can tell me the date, time and location it was taken from then I could generate a heightmap of it and produce a terrain map in Rhino 3.0. Feature heights could be read off of the heightmap and elevations and depressions would be visible on the terrain map. It would only take me twenty minutes to do.
Rick
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Rick Evans
http://www.freewebs.com/revans_01420/
The moon speaks Octave...
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photonovore
Moonatic
Reged: 12/24/04
Posts: 2792
Loc: tacoma wa
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Rick, I was hoping you'd volunteer that! 
Here you go:
waning
waxing
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Mardi
4" achromat, ETX-70, 8"cat.
Whitepeak Lunar Observatory Website
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revans
Carpal Tunnel
Reged: 09/26/05
Posts: 1637
Loc: Fitchburg, MA
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Mardi,
Here is a heightmap of the crater. Look at it in Photoshop and move the cursor over features of interest while reading the pixel values from the info window. I needed to use something as a reference datum so I picked the floor of Theophilus which seems to have a pixel value of about 87 in darker (lower) areas. The rim of the crater reads about 229 and we know that is about 4400 meters above the floor. Therefore, we can reference any feature on the map relative to the floor of Theophilus by this formula:
(feature pixel value - 87) * 40
By this method I calculate that Mons Penck has a pixel value of 252 at its peak. That would correspond to a height of 6600 meters above the level of the floor of Theophilus.
I'll do a terrain map from the heightmap and post that here presently...
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Rick Evans
http://www.freewebs.com/revans_01420/
The moon speaks Octave...
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desertstars
Reged: 11/05/03
Posts: 41911
Loc: Tucson, AZ
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Is the area around/adjacent to Mons Penck lower than the general area? If so, could that have "tricked" the instrumentation in some way?
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Thomas Watson
Author of Mr. Olcott's Skies. Available in paperback and ebook from Amazon and Barnes & Noble.
@desertstarsbks
Under Desert StarsEither Way, It's Reading
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revans
Carpal Tunnel
Reged: 09/26/05
Posts: 1637
Loc: Fitchburg, MA
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Mardi,
Here is the terrain map made in Rhino 3.0 from the heightmap I posted above...
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Rick Evans
http://www.freewebs.com/revans_01420/
The moon speaks Octave...
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revans
Carpal Tunnel
Reged: 09/26/05
Posts: 1637
Loc: Fitchburg, MA
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Mardi,
If you would like a close up of Mons Penck on the terrain map or a view from a different angle, let me know and I'll send it along.
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Rick Evans
http://www.freewebs.com/revans_01420/
The moon speaks Octave...
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photonovore
Moonatic
Reged: 12/24/04
Posts: 2792
Loc: tacoma wa
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Tom, that's what the concensus is playing out on the Lunar Observer's yahoo! board where i also posted the question. May be...but I have to wonder as the area Clementine highlights seems to be so distinct and limited in size. But let's look at the data Rick contributed and see if that supports a resolution issue with the Clementine data...
Rick, wow, excellent data, thanks so much! I took the heightmap you posted and posterized the image and what resulted appears to represent a sort of topo map of the area with pixel relationships (and thus elevations) grouped and deliniated...makes it easier to interpret, no?
 (original image; Rick Evans)
It appears that there is indeed a depressed zone more or less surrounding Mons Penck on the three sides towards Theophilus. Perhaps it is a resolution issue after all.
The heightmap...is this generated from the software that the dome people developed>? I could see some great uses for this in conjunction with controlled posterization to make an easier to read gradient map out of it.
I'm still kind of skeptical about the cause of this anomoly being wholly a resolution issue. If it was, wouldn't the whole area, Mons Penck *and* the surrounding depressed area, show as one, bigger depression? But the Clementine image seems oddly to confine just Mons Penck to the lower blue shading within a sea of higher green. 
There's still something I'm not getting I think. Though the LIDAR shows Mons Penck as depressed, the relief maps generated from the Clementine data show it as a clearly elevated feature, which, of course, it is. I guess the reason this question is important for me to resolve is that if I am to use LIDAR data in the future, then I need to know what sort of errors it's subject to and why and in what sort of situations they occur.  I think this is still inadequately explained although at least we're coming up with some theories to examine...
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Mardi
4" achromat, ETX-70, 8"cat.
Whitepeak Lunar Observatory Website
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revans
Carpal Tunnel
Reged: 09/26/05
Posts: 1637
Loc: Fitchburg, MA
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Mardi,
Posterizing was a great idea! I've never tried it before, but it is like a topo map!
The heightmap generator is just a simple plug in for Photoshop. If you are interested in trying it out, it is simple to use. You can get a 10 day free trial at:
http://www.cgsd.com/bumptexture/
They seem to have a monopoly on the filter though and if you want to buy it, it's rather expensive.
I'll attach a close up of Mons Penck as it does indeed seem to have a significant valley at its feet facing theophilus (unless this is an artefact of shadow in the original image... that could be ruled out by making a heightmap and terrain map of image b that you supplied. If I get a chance, I'll work up that image as well. The work above was only on image a.
Thanks again for the posterizing idea... that is what is so good about this forum... someone always sees things from a slightly different perspective and great ideas come forward!
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Rick Evans
http://www.freewebs.com/revans_01420/
The moon speaks Octave...
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revans
Carpal Tunnel
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Posts: 1637
Loc: Fitchburg, MA
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Mardi,
It seems like I always make a math error with my multipliers... the multiplier should be 30.99 instead of 40 in my heightmap calculation above...
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Rick Evans
http://www.freewebs.com/revans_01420/
The moon speaks Octave...
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photonovore
Moonatic
Reged: 12/24/04
Posts: 2792
Loc: tacoma wa
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Oh the multiplier accuracy isn't a problem, but thanks...just loooking at the relative elevations this time.
Yes, 500$ for a plug-in, oh my! So how does this pricey 'shape-from-shading' plugin compare to the similiar GIMP plugin you mentioned using with rhino in another thread? I like the free part of the latter package! 
"that is what is so good about this forum... someone always sees things from a slightly different perspective and great ideas come forward!"
Funny--I've been thinking the same thing for some time now...!
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Mardi
4" achromat, ETX-70, 8"cat.
Whitepeak Lunar Observatory Website
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revans
Carpal Tunnel
Reged: 09/26/05
Posts: 1637
Loc: Fitchburg, MA
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Mardi,
Unfortunately the GIMP filter was designed for satellite imagery of Mars and I encountered problems setting the camera parameters for telescope work. I think that for a good heightmap, the CGSD filter for Photoshop is the only game in town. I finally purchased it, but it was painful at that price!
Also, I would like to use your images waning and waxing (of the Theophilus region) in the project methodology for our hi resolution lunar imaging study. Would you have any objection to me including one or both of these images in the project methodology outline we are about to send out to the dozen or so project participants. Stuart (aka Gandalf) would like to send the methodology out in the next day or two as imaging is supposed to begin in January.
As an aside, would you be interested in joining the project? I could e-mail you the draft methodology to look over...
Rick
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Rick Evans
http://www.freewebs.com/revans_01420/
The moon speaks Octave...
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revans
Carpal Tunnel
Reged: 09/26/05
Posts: 1637
Loc: Fitchburg, MA
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Tom,
It wouldn't surprise me if there was a gap in the elevation data for the area on USGS charts... every Clementine DEM I've seen has gaps in the data much like this one for copernicus (elevation data gaps shown as black patches). This will not be corrected until 2008 when a lidar probe will fill them in...
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Rick Evans
http://www.freewebs.com/revans_01420/
The moon speaks Octave...
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photonovore
Moonatic
Reged: 12/24/04
Posts: 2792
Loc: tacoma wa
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Rick, thanks for all the info. This has been very illuminating. I think the final upshot is a data issue with the Clementine LIDAR maps. Now I can get on with my multi-ring basin studies.
The images I used (waxing waning) are crops from the CLA (Consolodated Lunar Atlas) as noted. So feel free to use them as you wish.
I don't have the equipment or the location to be of much use in high resolution imaging, however I would like to follow along with your project; sort of informally audit the group's progress if possible. I am always interested in new data sources and it looks like this will be an example of that!
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Mardi
4" achromat, ETX-70, 8"cat.
Whitepeak Lunar Observatory Website
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revans
Carpal Tunnel
Reged: 09/26/05
Posts: 1637
Loc: Fitchburg, MA
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Mardi,
Just a quick note on the price of the shape from shading filter (a heightmap generator plugin for Photoshop) from CGSD. It is currently sold as one component of their larger BUMP Texture Tools package. I spoke to the vice president of the company today and explained to her that many amateur astronomers might be interested in buying the shape from shading filter but would have little use for the other material and would definitely not want to spend $500 for the whole package. I asked if CGSD would consider selling only the shape from shading filter plugin and charge a lot less money!
She suggested the following. Those interested in just this one filter should send an email to sales@cgsd.com with a cc: to rwl@cgsd.com
The email should say that you are just interested in purchasing the shape from shading filter and should specify how much you are willing to pay for it. She thought that it might be worth it for their company to break new ground in the amateur astronomy market by offering a much more affordable option.
Anyway... I am not affiliated with CGSD in any way and just pass this along for what it is worth...
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Rick Evans
http://www.freewebs.com/revans_01420/
The moon speaks Octave...
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Adolfojose
super member
Reged: 02/07/05
Posts: 195
Loc: Managua,Nicaragua
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Even the Lunar Orbiter Photographic Atlas of the Moon name it Mons Penck:
http://www.lpi.usra.edu/resources/lunar_orbiter/images/aimg/iv_084_h3.jpg
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Adolfo
10" SCT MEADE LX50
TV Pronto on Tele-Pod Tripod and Tele-Pod Head
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Takahashi 102II(NSV)on WO EZ Touch Mount over a Oberwerk Wooden Tripod
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Stellarvue BV3 Binoviewer
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photonovore
Moonatic
Reged: 12/24/04
Posts: 2792
Loc: tacoma wa
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Quote:
Even the Lunar Orbiter Photographic Atlas of the Moon name it Mons Penck:
http://www.lpi.usra.edu/resources/lunar_orbiter/images/aimg/iv_084_h3.jpg
yeh, I don't know why Wood wrote "formerly known as Mons Penck..." 
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Mardi
4" achromat, ETX-70, 8"cat.
Whitepeak Lunar Observatory Website
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photonovore
Moonatic
Reged: 12/24/04
Posts: 2792
Loc: tacoma wa
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Just an update--Chuck Wood posted a response to my question on the Yahoo! Lunar Observer's group: "There must be some error with the Clementine topo there - it is definitely a local high spot."
Good enough for me: Case closed.
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Mardi
4" achromat, ETX-70, 8"cat.
Whitepeak Lunar Observatory Website
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