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Green/bluish colouring. Any suggestions what that could be ?

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Bent Erik Thomsen

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May 25, 2004, 6:27:33 PM5/25/04
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For a long time I have watched pictures from Spirit showing rocks parrly
cowered with blue/green colour.
I have seen no official discussion of these features (and hardly any here)

The picture below whows the most sharply coloured areas I have senn this far
?

http://www.lyle.org/mars/imagery/color/2-138253230-6.jpg

Please comment

Best Regards

Bent Erik Thomsen
Denamrk


Fox2

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May 25, 2004, 11:23:35 PM5/25/04
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The image at the URL appears to be 2 different images.

As for the color... I have heard that some types of rock exposed
to X-ray radiation change color.

Here is a color composite I did of one of the images.

http://members.cox.net/tucoan/pics/2P138253162EFF5300P2460L457.jpg

Fox2

"Bent Erik Thomsen" <bm...@poet.dk> wrote in
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marc

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May 26, 2004, 6:16:05 AM5/26/04
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Looks like a stero image to me.

marc

"Bent Erik Thomsen" <bm...@poet.dk> wrote in message
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jafar

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May 26, 2004, 8:57:52 AM5/26/04
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On Wed, 26 May 2004 11:16:05 +0100, marc wrote:

> Looks like a stero image to me.
>
> marc

No. It's just a very badly composited image. Fox2 has done a nice job of
putting it together especially considering, one of the filters used in
his image is from the Ultraviolet band. See his post below. :)

--
Jafar As-Sadiq Calley
Senior 1st Officer
Livewire Airlines
http://www.livewireairlines.com/

Fox2

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May 26, 2004, 2:41:52 PM5/26/04
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jafar <ja...@fatcat.delicats.net> wrote in
news:pan.2004.05.26....@fatcat.delicats.net:

> On Wed, 26 May 2004 11:16:05 +0100, marc wrote:
>
>> Looks like a stero image to me.
>>
>> marc
>
> No. It's just a very badly composited image. Fox2 has done a nice job of
> putting it together especially considering, one of the filters used in
> his image is from the Ultraviolet band. See his post below. :)
>

Thanx.

I like the 456 & 457 filters w/ 15-20% reduction of color saturation. It
gives the best color matches on the sundials. (Forget the sky, too much
UV, it always looks too bright & gives a blue or aqua cast to it.)

The Viking rgb pics are superior.

Fox2

BTW - what's wrong with the right camera filters??

jafar

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May 26, 2004, 3:52:51 PM5/26/04
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I just go for the 456 ones. I guess I'm lazy but it's too much faffing
about to get proper colours with the L7 data. L7 gives stupidly blue skys.
Mars can have very light blue skies on a clear day due to light scattering
but it's usually tinted light orange due to dust in the air. Don't believe
those official NASA pics with the uniform sepia skys. You can even see
they've painted the sky on if you zoom in on the horizon on their pics.

As for the camera filters. The ones they have now were designed more for
the science than the pretty pictures so we have to make do with the "close
enough" RGB of the current landers. The Vikings had analogue TV cameras
rather than lo res digicams so there was less distortion of the images in
regards to taking 3 separate images with filters while the shadows move in
each frame ;)

Anyway, I'd love to know what particular shade of blue you use when you
use the L7 filter. Do you also adjust the L4(red) and L5(green) to
compensate?

Fox2

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May 26, 2004, 5:45:03 PM5/26/04
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In article <pan.2004.05.26....@fatcat.delicats.net>, jafar <ja...@fatcat.delicats.net> wrote:
>On Wed, 26 May 2004 18:41:52 +0000, Fox2 wrote:
>
>> jafar <ja...@fatcat.delicats.net> wrote in
>> news:pan.2004.05.26....@fatcat.delicats.net:
>>
>>> On Wed, 26 May 2004 11:16:05 +0100, marc wrote:
>>>
>>>> Looks like a stero image to me.
>>>>
>>>> marc
>>>
>>> No. It's just a very badly composited image. Fox2 has done a nice job of
>>> putting it together especially considering, one of the filters used in
>>> his image is from the Ultraviolet band. See his post below. :)
>>>
>>
>> Thanx.
>>
>> I like the 456 & 457 filters w/ 15-20% reduction of color saturation. It
>> gives the best color matches on the sundials. (Forget the sky, too much
>> UV, it always looks too bright & gives a blue or aqua cast to it.)
>>
>> The Viking rgb pics are superior.
>>
>> Fox2
>>
>> BTW - what's wrong with the right camera filters??
>
>I just go for the 456 ones. I guess I'm lazy but it's too much faffing
>about to get proper colours with the L7 data. L7 gives stupidly blue skys.
>Mars can have very light blue skies on a clear day due to light scattering
>but it's usually tinted light orange due to dust in the air. Don't believe
>those official NASA pics with the uniform sepia skys. You can even see
>they've painted the sky on if you zoom in on the horizon on their pics.
>
True. NASA's been convinced for 30 years that Mars should be orange
everywhere. Looking through a telescope at Mars can settle that issue.

All in all, I am impressed with the mission & the quality of the images. I
hope that when they get Spirit into the hills, they go to 456 or 457 filters.

>As for the camera filters. The ones they have now were designed more for
>the science than the pretty pictures so we have to make do with the "close
>enough" RGB of the current landers. The Vikings had analogue TV cameras
>rather than lo res digicams so there was less distortion of the images in
>regards to taking 3 separate images with filters while the shadows move in
>each frame ;)
>
>Anyway, I'd love to know what particular shade of blue you use when you
>use the L7 filter. Do you also adjust the L4(red) and L5(green) to
>compensate?
>

I'm using PaintShop Pro 7 & it uses 'pure' r100 g010 b001 colors to combine
3 greyscale 8 bit images into 1 truecolor image. There is no adjustment for
the color values....unless you modify the 8 bit images before recombining.
(which I, some times on darker images, raise all 3 gamma levels 50%) :)

Fox2

____
Fox2

A psychologist is a man who watches everyone else
when a beautiful girl enters the room.

JusUK

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May 28, 2004, 3:41:41 AM5/28/04
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Fox2 <Fo...@f2.net> wrote in message news:yd8tc.36118$PU5.8145@fed1read06...

Nice picture fox2 but doesn't this still leave the original question, i.e.
what is that blue colour (rather than green)?


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CWatters

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May 28, 2004, 9:08:05 AM5/28/04
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"Bent Erik Thomsen" <bm...@poet.dk> wrote in message
news:40b3c866$0$252$edfa...@dread12.news.tele.dk...
> For a long time I have watched pictures from Spirit showing rocks parrly
> cowered with blue/green colour.
> I have seen no official discussion of these features (and hardly any here)
>
> The picture below whows the most sharply coloured areas I have senn this
far

That picture looks faulty so I'll ignore it for now... However they have
already established that some rocks are _very_ blue on the inside but are
covered by red/brown dust. For example see these images of blue rocks where
the RAT has removed the dust....

http://mars.hynee.com/spirit-sol-86.html

http://mars.hynee.com/spirit-4.html

When you see what looks like a "blue covering" it's probably a blue rock
with it's red dust covering blown off the top..


Hynee

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May 28, 2004, 3:45:27 PM5/28/04
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"JusUK" <j...@TRAPtravel-diary.de> wrote in message
news:_YCtc.28$ZT5.16@newsfe2-win...

For the sake of argument, here's my version of the picture...
http://users.tpg.com.au/hynee/mars/138253162-rgb-4567.jpg
[ I make mars.hynee.com , but at the moment I'm out of webspace. If/when I
upgrade, it will be at http://mars.hynee.com/spirit-sol-134.html . I've got
about 50MB of data waiting to go up!]

Bent, you've definitely got an incorrect frame there. Fox2, you should
fiddle with the colour balance. The rovers contrast stretch all images they
send back, so the brightest pixel is 100% and the darkest 0%. That means
that blue red or green may be over-bright when you combine 3 frames.

For comparison, here is the sundial image from the same sol:
http://users.tpg.com.au/hynee/mars/138253804-rgb-234567.jpg
It's a little yellow, but that's OK, I think there's a fair amount of dust
on it, and the sunlight that filters through is probably yellow too from the
dust.

Finally, here's a money shot:
http://users.tpg.com.au/hynee/mars/138344966-rgb-234567.jpg

A fantastic shot of one of the columbia hills.You can see I used all
possible filters for it (L2 through L7). This is from sol 135, I think
Spirit was 700m away at the time.

--James
mars.hynee.com


Bent Erik Thomsen

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May 28, 2004, 5:41:26 PM5/28/04
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"Hynee" <hy...@tpg.com.au> wrote in message
news:40b7...@dnews.tpgi.com.au...


Beautifull picture of the Hills !
I look forward to see the remaining 49 MegaBytes.

----------

But back to my initial question.
OK the picture referenced was clearly a tchnical calimity, but , but.

I still seek som comments on what the blue/green surface colouring of many
rocks (and sand) could be ?.

I wonder why nobody has commented on it yet (or have I missed it?)

I also wonder (very much) why there is abselutely no comments on the
ice-like structures in Endurance Crater?
Any bookmakers offering bets whether it is Water Ice or not ;-)


best regards

(and a silent hope for more traffic here)

Bent Erik Thomsen
Denmark


Paul Victor Birke

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May 28, 2004, 7:52:09 PM5/28/04
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you are a guru, amazing images

well done

paul

Paul Victor Birke

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May 28, 2004, 7:52:44 PM5/28/04
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you are a guru, amazing images

well done

paul

nonl...@rogers.com

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May 28, 2004, 7:54:54 PM5/28/04
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This message was cancelled from within Mozilla.

Fox2

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May 30, 2004, 6:33:46 PM5/30/04
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Here is the same pic w/ just 456.
Yup! there is dust on the sundial. :)
http://members.cox.net/tucoan/pics/sp-sol134-09-456.jpg

Fox2

>Finally, here's a money shot:
>http://users.tpg.com.au/hynee/mars/138344966-rgb-234567.jpg
>
>A fantastic shot of one of the columbia hills.You can see I used all
>possible filters for it (L2 through L7). This is from sol 135, I think
>Spirit was 700m away at the time.
>
>--James
>mars.hynee.com
>
>

____

JusUK

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Jun 2, 2004, 3:32:59 AM6/2/04
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CWatters <colin....@pandoraBOX.be> wrote in message
news:VQGtc.135919$6p.69...@phobos.telenet-ops.be...
Blue rocks, wow. I just thought it was some kind of false colour effect from
the imaging systems. Never seen a blue rock, combination of copper oxide and
sulfur?


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CWatters

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Jun 2, 2004, 3:23:48 PM6/2/04
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"JusUK" <j...@TRAPtravel-diary.de> wrote in message
news:bjgvc.32$xg2.18@newsfe1-win...

> Blue rocks, wow. I just thought it was some kind of false colour effect
from
> the imaging systems. Never seen a blue rock, combination of copper oxide
and
> sulfur?

I believe volcanos on earth sometimes produce blue glass but I'm no expert.


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