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Explaining the Mars Photo Colorization
TaddyPorter writes "I've seen stories going around the 'net in regards to NASA editing photos of mars. Mainly, the sundial used for calibration showed different colors than the dial on mars. While a wide range of explanations were taking shape, the Pancam Payload Element Lead for the mission, Jim Bell of Cornell University, was kind of enough to explain the color differences."
Actually, now it makes alot of sense. But that still won't stop the conspiracy kooks from claiming otherwise.
No boom today. Boom tomorrow. There's always a boom tomorrow. - Cmdr. Susan Ivanova
Supposedly they have a picture of Martians humping Beagle2, but they edited it to look like a plain stewn with rocks.
Sheesh, evil *and* a jerk. -- Jade
If blue appears pink on Mars, what is the real color of the little green guys?
They could have used a Foveon Sensor if they didn't want Bayer interpolation.
I don't trust him.
His website was taken down immediatly after slashdot posted this.
His "truth" couldn't stand up to the slashdoting scrutiny!
Yo Grark
Canadian Bred with American Buttering
Hmm...
Monday morning. Looks like everyone on the east coast went to their desks and got straight to work. I know I'm working hard now.
I mean, I'm color blind.
From end of article (yes, I skipped straight there... :))
There is simply no point in adding on their site "caution these images are not 100% precisely actual colors" when no digital image is really 'actual colors'.
Quite. In fact, I'd go as far as to say that NASA expected most of the people who were scrutinising these pictures to have some experience with astronomical imaging, where almost nothing is "true" colour in that sense.
Personally, I'm in favour of as much rebalancing as it takes to make the images pretty. If they don't make full use of my eye's ability to perceive them, then what was the point of spending all that money obtaining them in the first place? So long as the raw originals are available too, who cares?
These sigs are more interesting tha
I have a Sonly Clie' PDA with a digicam built in, and it can be used to demonstrate how digicams "see" color differently, especially in the near-infrared range.
If you go into the camera application and aim the Clie' at an infrared remote control (like a TV or stereo remote), and hit one of the buttons on the remote, the PDA camera will pick up the infrared and actually display it visibly!
The bizarre claims of conspiracy theorists just go on and on. If you go to their websites you can read more than any brain can handle. I have read literally dozens of things that ``prove'' the moon landings were faked, for example, and each one is rather easily shown to be wrong by anyone with experience in such things.
I think the problem here is twofold: we tend to want to believe (or at least listen to) conspiracy theories, particularly to do with space. Also, the evidence is presented in such a way that, if you are unfamiliar with the odd nature of the vacuum of space and of space travel, it sounds reasonable.
>>esr>>
Zero to Slashdotted in 8 posts!
Is anyone able to pull the article from their cache and post the text?
Quote from ???: "There are lies; there are damn lies; and there are benchmarks."
I'm glad he was "kind of enough" to explain that... maybe someone should "kind of" use grammar check next time.
Ya know, this whole mars thing... What if the pictures they are capturing show up with these little green martian men just like in the cartoons... I mean.. do you really think they would tell us? No, of course not - so then whats the point of the whole mission?
Don't Tread on Me
...doesn't NASA throw the public a bone? This color correction controversy pops up everytime a probe successfully lands on Mars and sends pictures back. One would think that they would have a standard RGB style camera for publicity shots. Chances are they can only afford to put on cameras practical for the mission, but I still believe a better solution could be provided. It probably just wasn't important to them... ;) Perhaps next time a camera could be included that features lens that provide scentific data and that can double as a publicist for NASA - spitting out RGB standard images that require no color correction.
Fun with Inkwell | www.coo
Mirror here...
The tyrant was brought down with the fastest advacing and the most successful military operation in the history of warfare?
Here!
Aside of the odd colors, I found this one of the most interesting anomalies in the pictures so far.
"Honey, I feel a certain distance between us..." "Really? A 31ms ping ain't that bad..."
TOP STORY: NASA Is Not Altering Mars Colors.
Posted by: Kano
On: Sun January, 18 2004 @ 03:34 GMT
This article is a brief summarised explanation of how the PanCam on the Mars Spirit Rover operates, in relation to the strange appearance of the calibration sundial in some pictures. The question was first raised by ATS member AArchAngel, and has been discussed at length in this AboveTopSecret forum thread and ATSNN story:
thread
Mars Spirit Rover Picture analysis.
In this thread I will attempt to summarise my posts to the larger thread.
What are you talking about?
Ok, the initial alarm was raised after it was noticed that the color-calibration sundial mounted on the rover, looked quite markedly different in the Mars-Panorama shots compared to its regular appearance.
Immediately wide-ranging theories began to pop up. At this stage I knew very little of the particulars of the PanCam so I decided to go and see what the Horses mouth had to say. I sent out a swag of emails to the NASA marsrover team, the Athena Instrument team at Cornell University, and the long shot, an email to Assoc. Professor James Bell. Who is the Pancam Payload Element Lead for the mission.
Now, getting no response from the Athena team, and an automated response from the NASA team. I was amazed and delighted to see that Dr. Bell had indeed taken the time out of his busy schedule to help explain this quirk in the panorama pictures. His email response is below:
quote:Thanks for writing. The answer is that the color chips on the sundial have different colors in the near-infrared range of Pancam filters. For example, the blue chip is dark near 600 nm, where humans see red light, but is especially bright at 750 nm, which is used as "red" for many Pancam images. So it appears pink in RGB composites. We chose the pigments for the chips on purpose this way, so they could provide different patterns of brightnesses regardless of which filters we used. The details of the colors of the pigments are published in a paper I wrote in the December issue of the Journal of Geophysical Research (Planets), in case you want more details...
All of us tired folks on the team are really happy that so many people around the world are following the mission and sending their support and encouragement...
Thanks,
Jim Bell
Cornell U.
Now, as far as the pink tab where the blue one should be, that email is infact the complete answer. But its not easily understandable to the layman. Below I will attempt to explain why this occurs.
Click here to read comments or post your own.
Displaying the first 12 replies to this news story...
Posted by: Kano
On: Sun January, 18 2004 @ 03:35 GMT
Digital Cameras
Firstly, we need to understand how the PanCam, and indeed digital photography in general works.
Luckily for us we have our good friends at http://www.howstuffworks.com to turn to.
How Digital Cameras Work
It would be worthwhile to read the entire article on howstuffworks, for a fuller understanding of the processes at work. But because I know you are all busy (lazy?) I will summarise.
Basically, the heart of a digital camera is the charge coupled device or CCD. This CCD converts light hitting it into electrical impulses, the brighter the light, the stronger the impulse. Now, CCD's are color-blind. All they do is signal how bright the light hitting them is. All well and good for black and white photography. But for color we need to do more. To get a color-picture. We need to record images via the CCD using a series of 3 filters. A Red filter, a Green filter, and a Blue filter. These are then recombined afterwards to give a color-representation of the picture. (Note, cheaper options like the Bayer filter pattern are often used in commercial digital cameras, but they use interpolation and are subsequently less accurate than 3-filter methods.
Never True Color
Quite a big deal has been made o
Make even shorter URLs - 8LN.org
we need a website torrent" system
Shouldn't that have been: ;-)=
"I am colorblind you insensitive clod?"
Well its OK, if Nasa wants to change the colors. No fuzz.
But can they tell if they do that and also provide pictures with alternative coloring so that the recipient have choice.
That would seem reasonable to me.
They can do that, and still Edit away all the alien artifacts...
Sorry, I don't have anywhere to mirror this with images and all (anywhere that would survive an /. that is ;) )
TOP STORY: NASA Is Not Altering Mars Colors.
Posted by: Kano On: Sun January, 18 2004 @ 03:34 GMT This article is a brief summarised explanation of how the PanCam on the Mars Spirit Rover operates, in relation to the strange appearance of the calibration sundial in some pictures. The question was first raised by ATS member AArchAngel, and has been discussed at length in this AboveTopSecret forum thread and ATSNN story: thread
Mars Spirit Rover Picture analysis.
In this thread I will attempt to summarise my posts to the larger thread.
What are you talking about?
Ok, the initial alarm was raised after it was noticed that the color-calibration sundial mounted on the rover, looked quite markedly different in the Mars-Panorama shots compared to its regular appearance.
Immediately wide-ranging theories began to pop up. At this stage I knew very little of the particulars of the PanCam so I decided to go and see what the Horses mouth had to say. I sent out a swag of emails to the NASA marsrover team, the Athena Instrument team at Cornell University, and the long shot, an email to Assoc. Professor James Bell. Who is the Pancam Payload Element Lead for the mission.
Now, getting no response from the Athena team, and an automated response from the NASA team. I was amazed and delighted to see that Dr. Bell had indeed taken the time out of his busy schedule to help explain this quirk in the panorama pictures. His email response is below:
quote:
--------
Thanks for writing. The answer is that the color chips on the sundial have different colors in the near-infrared range of Pancam filters. For example, the blue chip is dark near 600 nm, where humans see red light, but is especially bright at 750 nm, which is used as "red" for many Pancam images. So it appears pink in RGB composites. We chose the pigments for the chips on purpose this way, so they could provide different patterns of brightnesses regardless of which filters we used. The details of the colors of the pigments are published in a paper I wrote in the December issue of the Journal of Geophysical Research (Planets), in case you want more details...
All of us tired folks on the team are really happy that so many people around the world are following the mission and sending their support and encouragement...
Thanks,
Jim Bell
Cornell U.
-------
Now, as far as the pink tab where the blue one should be, that email is infact the complete answer. But its not easily understandable to the layman. Below I will attempt to explain why this occurs.
Click here to read comments or post your own.
Displaying the first 12 replies to this news story...
Posted by: Kano
On: Sun January, 18 2004 @ 03:35 GMT
Digital Cameras
Firstly, we need to understand how the PanCam, and indeed digital photography in general works.
Luckily for us we have our good friends at http://www.howstuffworks.com to turn to.
How Digital Cameras Work
It would be worthwhile to read the entire article on howstuffworks, for a fuller understanding of the processes at work. But because I know you are all busy (lazy?) I will summarise.
Basically, the heart of a digital camera is the charge coupled device or CCD. This CCD converts light hitting it into electrical impulses, the brighter the light, the stronger the impulse. Now, CCD's are color-blind. All they do is signal how bright the light hitting them is. All well and good for black and white photography. But for color we need to do more. To get a color-picture. We need to record images via the CCD using a series of 3 filters. A Red filter, a Green filter, and a Blue filter. These are then recombined afterwards to give a color-representation of the picture. (Note, cheaper options
---- Take the Space Quiz!
The questions are, of course,
- if there is a tinted color light source, what would the color target display on a normal color target? What would it show via the camera with the tinted light source
- The sun is the same light source on mars as it is on earth, therefore it should be easy enough to take a solar spectrum and see what the degree of tinting is.
- With an atmosphere at 1% or less of the earth, the spectrum could nearly be the same spectrum as in a vacuum
- if the spectrums are essentially similar, then the color targets should be the same, say as on earth or in vacuum, given a clear day without dust and clouds, etc.
- Of course,there is also the matter of the end result of different photo filters getting mis interpreted. However, JPL has published some pictures with red skies, and some with blue skies, as this item from the tin foil hat crowd. This has contributed to the controversy.
See also this earlier slashdot story on the Mars SundialsSo it looks like this particular annoyance has been around for a while.
"It is a greater offense to steal men's labor, than their clothes"
Not to mention that this mars mission was planned before GWB was even 'elected'.
I don't know what you guys are talking about. Those colors all look fine to me. Mars looks exactly like it did when I was last there...
Wow, do we really need another thread about article about the infamous Mars colonization. We already discussed this in the last one. It's all about filters used. When blue-according-to-the-human-eye turns extremely red, well, that's obviously when they aren't using a filter to reflect colors as seen by the human eye best, but to enhance other wavelengths. I don't really see what the problem is, and why this of all technical stuff has to be so mysterious.
The link in the article is of course slashdotted now, so here's another one explaining how a camera on the rover works:
The Panoramic Camera (Pancam)
Pay particular attention to the last paragraph there.
Beware: In C++, your friends can see your privates!
Australian outback ey? Before you know it we'll have red-tinted shots of Hobbiton and Mount Doom popping up on the NASA site too.
> The tyrant was brought down with the fastest advacing and the most successful military operation in the history of warfare?
Fastest advancing? Dude, it took them three whole movies to finish that shit up! And what was with that boat trip at the end?
The real reason we've seen no Martians. Nobody knows the proper way to read home pregnacy tests there. They all died out.
Does anyone know when "The Moon Landing Special Edition" will be out on DVD?
I heard someone just bought the rights to do a big-budget remake sometime this decade. Betcha it's not as good as the original though.
Meesa jar-jar-Bush!, erm, etc.
These sigs are more interesting tha
Just presidential courtesy. You set the other guy up for a few lies ahead of time, and he is expected to do the same, regardless of who is elected. Of course if possible, you are trying to set it up for your own party.
That's just paranoid. The real reason they are colorising the images is because the Viking landings were faked, and now all the images from successful landings have to be altered to look like the Viking images, just to hide the sinister truth.
If I seem short sighted, it is because I stand on the shoulders of midgets
How did that get modded up? The conspiracy bitches complain about the color correction then complain more when it's explained in too much detail?
Mars Climate FAQ:
s as well.
- Why isn't the Martian sky blue like the Earth's?
That page includes images using colors-close-to-what-a-human-eye-would-see-them-a
Beware: In C++, your friends can see your privates!
I think NASA have edited out the sky to a pale pink colour. Take a look at the 12MB full panorama, and see how the horizon suffers from the jaggies.
Don't feed me any rubbish about JPEG compression, because JPEG doesn't do that. The raw image from the camera should be naturally anti-aliased: where a boundary crosses a CCD pixel, that pixel will receive a weighted average of the light from either side of the boundary.
The sky is unexpectedly uniform over the entire panorama - where's the sun?
Ydco co
It'd be interesting to see the raw image data but I expect that without software manipulation it'd be a pointless excercise.
Worst
I know my digital camera has settings for getting true whites under florescent or incandescent lighting, but what do you do when your natural light is pinkish-yellow?
Subtly adjusting the Mars photos is no big deal when you consider how much color is made up for the shots of galaxies, nebulas and other deep space bodies. Those shots are often black and white to begin with!
Here is the unedited photo of Beagle, just after said events took place...
Yes, it was supposed to be funny. First it got modded "Interesting" wich was rather confusing to me and now it's a Troll. Actually it was neither. Well, nevermind! Hey! At least someone got it! ;-)
Kano's self-composed thread was about as long as Joe Clark's web accessibility discussion. Thanks, Kano!
Wasn't there a Sony camera awhile back that could see through clothing because it was ir sensitive? Gave the up-skirt crowd a thrill.
The images are not recolored to "make them look pretty."
There are two main reasons for the color shifts.
Reason one, some of the images are taken lower in the IR spectrum, and the pigments on the sundail are desighned to react differently in that part of the spectrum.
Reason two, all the images sent back have their individual RGB channels normalized, which is similar to using "auto levels" in photoshop.
But the important factor is this: the sundail has a mirror which shows both the sky & the ground, and has full white & black reagions, meaning that even a normalized image will come through unscathed by color changes. These colors are then used to match colors for the rest of the images.
Bottom line, the colors we see are as accurate as can be gleaned, not just made up to look pretty.
(You can test this with digital camera images of your own. Run Auto Level on them (which equalizes the color channels). If there are images that full of color, but have no areas of pure white & pure black, you'll likely get some whacky colors. I have a picture of the Charles river with blue sky, green grass, and purple water)
What were you expecting?
For sure I can see the infrared too if I look very closely. It just looks like a very dim red glow, though, nothing interesting.
Tim
Omnia vestra castrorum habetur nobis.
Bush Sr. announced the same 'going to mars' thing, it didn't happen. It's not happening this time, either.
Blue of course! The night sky is the same color as the day. Just not as bright and we see it as black (At least if you're not in a city). The sky on mars will not be blue. The atomsphere is much less dense than earth so the scattering of light will be much less. The Martian atmosphere contains more dust and much less water than earth. When I look at the ground portion of the images, the ground and rocks are colored appropriately. The groud greatly resemble many places in the southwest, with the exception of the total lack of plant life. SOme images of the sahara desert would be indistinguishable except for the overall color due to the different minerals and sky color.
When I was young, I had to rub sticks together to compute.
Forget Mars.
Explain to me how Uranus got to be that color!
can't resist... must post Uranus joke
Does anyone know when "The Moon Landing Special Edition" will be out on DVD?
Check out the boxed HBO series "From The Earth To The Moon". Some of the effects are better, and there are definitely some better "3rd person" shots of the lunar astronauts doing stuff.
On the other hand some of the effects are cheesier -- the view out the LM window of the lunar touchdown is clearer, but this time they let the kicked-up dust billow in an obvious reaction with surrounding atmosphere, rather than just radiating straight out the way it did in the original (as it would in vacuum). (Oh, and some of the moon walking has problems too -- they did a good job rigging the astronauts to simulate a 1/6 G bounce-walk, but the dirt they kick up still falls back at an obvious 1G rate. The original did it much better and simulated the dirt at 1/6 G too.)
(Seriously, if you haven't seen that HBO series recently, do yourself a favor and find it and watch it. Good stuff.)
-- Alastair
Why did you post a link to a picture of your face?
The whole mars lander thing is a fake, I admit it. I cooked it up on a red rocky diorama in my basement, and a computer. NASA hired me so they could get some good PR.
C'mon... who cares?!
I can't see in infra-red.
When you insist on using this for the "red" channel in your images the color will always be wrong. Who do I have to work over with a 2x4 to get people to understand this?
As the article states - instead of throwing away wavelengths above the visible spectrum (as the human eye would do), they are instead clamped. Anything bright infra-red becomes bright visible-red. Net result - way too much red in the pictures.
I don't give a damn about "scientific data" produced by including infra-red.
What color would the mars ground and sky appear to my own eyes if I were standing on Mars? I can't see in infra-red, so why are you including that in your "visible" images?
Love,
AC.
You haven't killed us yet! But almost. The slashdot activity has certainly slowed us down, but we're not out. Thanks for your interest in this story, we're not like all the other tin-foil-hatters out there... we don't believe every conspiracy, which is why we worked hard to quickly debunk this one. We're redirecting today's traffic to a static HTML version of the article (thank you mod_rewrite) so we're still up... but slow. Enjoy.
The Red-Eye Reduction setting doesn't work on Martians then.
You don't need a lab to make mud.
The real reason of course is much more obvious. The greens in the picture are being filtered out. This is to obscure the algae that they are finding. The full picture won't ever come to light but we may know more once Bush has decided whether the algae are intelligent or not, how well armed they are, whether he should buy / sell arms to them, before / after launching an attack of his own. Learning from the Iraq war he is avoiding the "I told you so" phenomena. Please join me in sending a note to the whitehouse apealing: THE ALGAE ON MARS HAVE NO WMDs. Why did that other US probe crash again?
Not to do anything crazy like bring the artcle into the conversation, but the uncalibrated RGB raw data that the mars rover sends back, and the methods used to color correct it reminds me of this:
The Russian Record
This brilliant Russian photographer in the late 1800s/early 1900s took an amazing number of photographs, and he would photograph everything three times, with a red, blue and green filter.
He would then use a special triple projector with the appropriate color filters to show gorgeous color images, long before the invention of color film.
So today, we can put these images back together in Photoshop, but we have the same Mars problem, we have three color channels, but no clear idea how they relate to each other.
Lacking a color-calibration sundial, we have to rely on our knowledge of skin tone, sky color, etc to tweak these colors. The link above has a link to the raw files in the Library of Congress, for geeks who want to recomposite some of their own.
What were you expecting?
Why isn't the Spirit team using the L4 filter?
The L4 filter passes light at 600nm, right on the red channel for RGB. Combine that with L5 + L6 and we have a perfect RGB channel image to end all this bickering.
Yes, it would be a narrower frequency band and less scientifically interesting because of the lack of sensitivity in the near infrared. Yes it would be affected by colour absorption in the martian atmosphere. Yes it would be an RGB channel image rather than a true human visual image (no digital image can be). But it would be the closest thing to the kind of snapshot a human standing on mars with a digital camera would take. It would be something we could all relate to directly.
I thought that the whole idea with Spirit was to make it anthropomorphic: binocular vision, 1.5 metres tall, mobile, etc. So why not do a couple of panoramas in RGB? Why not look around before launching into the science?
In fact, Spirit has taken a couple of images with L4, but mainly for calibration against the sundial or as part of a test rotation through all filters. Almost all of the component images for the panoramas are taken with L2, L5 & L6, resulting in the present confusion when these are mapped back into an RGB image. So we know the L4 filter works.
except Hobbiton + Mount Doom (in fact the whole of the LOTR trilogy) were all shot in New Zealand, which while being close-ish to Australia, is a fair way from being in the Australian Outback.
But then again, wasnt there a stat that something like 85% of people from the USA couldn't locate Canada on a world map? so this doesnt really surprise me.
I mean, they spent a lot of money on that camera, it seems a piddly thing to leave out of it and the comm protocol for sending the pictures.
THIS THING CAN TURN ON A DIME, MACROSSZERO STYLE ALSO FUCK BETA, ~NYORON
You can't just combine grayscale images from the L2, L3 and L5 filters to get a color in between ("true" red).
They have widely varying response curves all over the visible spectrum. Combining them all will make a huge, lumpy response curve centered somewhere around the red visible, but emcompassing and emphasizing frequencies well outside it!!! It will be completely unrepresentative of what the eye would see on Mars. The same goes for all the other simple mixing he's doing, adulterating the other bands.
The filter response for L1-8 are NOT notch filters people, they have defined curves. Two of the filters are specifically wide band responses as well. And the human visual response curves are equally important.
No, what he SHOULD have done is essentially what Nasa did, which is to solve a minimization problem matching up weighted averages response curves from the available filters to the red/green/blue response of the human eye, and taking the combination with least squared error.
But apparently he was too simple-minded to realize this. And also that NASA saturated all of their pictures on tranmission to reduce error (and the exposure settings are nowhere to be found), so you have even less information to go on.
He just kept the combinations he "liked", method be damned. Nasa did the same thing for the press. His colors are not "correct" and your arguments hold no water (oh, I'm sorry, MUD) if you cite him as authority.
THIS THING CAN TURN ON A DIME, MACROSSZERO STYLE ALSO FUCK BETA, ~NYORON
divided into parallel channels by a strong surface wind. It's fairly evident by the even spacing that the formation has a uniform density. I believe the prevailing flow is SW to NE (assuming up is "north") because of a small, secondary ridge of accumulated material on the NE side of the formation. As wind blows particles from the slopes of the channel and down the backside, some is desposited and builds up upon itself on the plateau behind it.
You can tell its wind-based by the similar bottom-left to top-right streaks all over the landscape.
Very cool, but definitely not organic. You would see this kind of thing at the beach if we have hurricane force winds all the time.
THIS THING CAN TURN ON A DIME, MACROSSZERO STYLE ALSO FUCK BETA, ~NYORON
makes me think all kinds of credible.
No wait, it looks like a hack-job whacko's website!
Not the first time I've seen it pushed here.
If detailed analysis means he would take each raw exposure image of the "machinery" and, considering the response curves, building a likelyhood estimate model of the chemical composition due to reflectivity across various bands, and produce a list of likely material compositions...
Oh wait, he's making speculations based on what it "looks like" from a grainy photo?
Give me a fucking break. I have a paperweight that kinda looks like Jesus when the sun is setting. Interested?
THIS THING CAN TURN ON A DIME, MACROSSZERO STYLE ALSO FUCK BETA, ~NYORON
if the colors are less red because of white-balance/normalization issues as suggested by contrast differences between images with pure white vs. images without:
1) the images with white, like the cleaner airbags, would show the planet as it should, as each filter would contain the same normalization calibration from the presence of white light. Images pieced together with the raw data do NOT match the press-released images in these instances.
2) The sky in the images reconstructed from raw data should show up as almost perfectly white. In most all instances, it does not. It appears quite cyan to light blue.
I'd rather believe the guys at NASA honestly believe they are providing the press with what they believe are the correct colors, and are simply clueless when it comes to photography. Great engineers and scientists they may be, but photographers they are not.
Xiphos
But then again we both know that those shots actually don't look anything like the Australian outback either, do they? So the next time you decide to be a wise-ass remember to suspend your disbelief and bear in mind that sometimes some people just try to be a little light-hearted rather than acting like snotty little teenagers suffering from existential angst and on a mission to show the world how clever they are.
"Blue" does not appear "pink" on mars. The *CHEMICAL* they used to make the "blue" chip is "blue" to human eyes in normal lighting conditions because it reflects "a lot of the light in the blue part of the spectrum". The *CHEMICAL* is also "very bright" in the "near infra-red" which is *outside* the range of normal human vision. (Hence "infra-red" and not just "red" 8-).
The scientists are interested in the near infra-red, and infra-red is way on the other end of the spectrum from blue.
So they used the filter/sensor that is responsible for "seeing" the color red and widened it to see "near infra-red". Since all that data comes back as "the red part of the picture" and the piece of plastic "looks pink" because there is a lot of signal in the "red part".
Keep in mind that you cant see "near infra-red" and neither can the NASA guys, and you monitor couldn't display it anyway so your dog would not be able to see it if you held him up in front of your monitor.
The very fact that the "blue chip" looks "pink" in the pictures IS DATA because if the martian atmosphere was filtering more infra-red the chip would look more bluish because there would be less signal on the red channel. Similarly if the martian atmosphere were blocking the blue spectrum more, then the chip would look more red and less pink. (and so forth...)
The ENTIRE POINT of the mars dial is that they can take the duplicate equipment here and put it in a room and vary the conditions until they duplicate the various signal levels. (Hence "calibrate" and its orthogonal concept.) Of course, since they know the exact traits of the chips and of the filters, they don't actually have to set up the room and do the test, they can just look at the numbers and do the math.
For the "very slow" among us; consider those nice "X-Ray Pictures" from the Hubble (and such). They are nice color pictures, but X-Rays don't have color. The scientific value comes from knowing what signal values represent what measurable scientific values. If the X-Ray pictures were photo-realistic in the visible spectrum they would just be black squares, which wouldn't help anybody know anything.
As for the "green question" green == green for whatever value of "green" the "green filter" is using. Since the near-green colors are all still in the visible spectrum, there is likely no value for them to have used any non-standard filters. Then again, they might have a whole filter set ready to show fractionals of the green spectrum as a full-color shot (just like the X-Ray pictures.)
This "Green" question was the whole point of that one photo-shopped earth-taken (mostly orange) picture of the smoke and fire. If you use your tools to "color correct" an image of a very narrow -colored image it can make details much more clear, but you get "blue flames" and such. Doing that after the fact sucks compared to actually changing the filters in the camera at the time of collection. When you do the photo-shop thing you are strengthing the weak signals. When you change your filters you are picking up more detail where you want or need to see it.
The fact that these data are then rendered visibly should surprise nobody.
It's just the jackasses that don't understand the difference between "visual representations of significant data" and "vacation snapshot" have decided to manufacture a tinfoil-hat issue for us to enjoy at our leasure.
Innocent people shouldn't be forced to pay for inferior software development.
--"Code Complete" Microsoft Press
Sorry about the hair-splitting, but this is Slashdot... ;-)
Debunking the "59 Deceits"
The hallmark of science is measurement, how f*ck do you measure "extraordinariness"?
Is claim X 2x more "extraordinary" than claim Y, or the other way around. What's the SI units for this quality?
STOP REPEATING THIS BULLSH*T!
BTW, I'm in no way saying that the parent poster is correct in believing those sand dunes are organic, but please drop this anti-scientific quote from your repertoire!
Debunking the "59 Deceits"
Lets see, color is just our cognitive perception of a particular region of the EM and If human eyes could register X-ray radiation...
So lets see, you admit that human eyes cannot register X-ray radiation, so they cannot cognitively preceive X-rays, and you understand that color is our cognitive perception, but you conclude that X-rays *DO* have color anyway..?
OK, X-rays have color, but in the exact same sense that cows would fly if they were a lot lighter and, um, had wings... 8-)
Simply put, X-rays exist across a section of the EM spectrum, so they may vary in frequency. Saying that in turns gives them the trait of "color" is sloppy and unhelpful.
Innocent people shouldn't be forced to pay for inferior software development.
--"Code Complete" Microsoft Press
we have this picture of the rover platform as seen from earth and on mars. with a distinct color shift noted.
"It is a greater offense to steal men's labor, than their clothes"