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Colorization of Mars Images?

ares2003 writes "There is no scientific reason, why JPL is colorizing Mars in that dull red tint as in their press release images. In the latest panorama image, there is a hint, that they deliberately altered the colors, as the blue and green spots on the color calibration target (the sundial) suddenly converted to bright red and brown. Source of original images: 1, 2 - (for highres replace "br" with "med"). At normal weather conditions, as we have at the moment, there should be a blue sky on Mars and earthlike colors. Furthermore the sky looks overcasted on the pictures as it cannot be considering the sharp shadows on the sundial. If the sky was overcast, then because of diffuse lighting, there would be no shadows. A few years ago, I did an investigation about that very same topic for the Viking and Pathfinder missions."

10 of 784 comments (clear)

  1. Check the links, editors by shystershep · · Score: 4, Interesting
    For more hard-hitting 'information' from the submitter of this story, visit his website: Alternative Areology and Archeology. Browse his conspiracy theories and check out his evidence of cities on Mars, spaceflight in ancient Indian Literature, and learn the secrets of the pyramids!

    Way to go, Michael.

    --
    The bigotry of the nonbeliever is for me nearly as funny as the bigotry of the believer. - Albert Einstein
    1. Re:Check the links, editors by s20451 · · Score: 3, Interesting

      Well, the truth is that NASA is well known for changing the colors in images. The spectacular images from Hubble are almost always in false (or exaggerated) color, though this is almost never acknowledged.

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      Toronto-area transit rider? Rate your ride.
    2. Re:Check the links, editors by TheCarp · · Score: 3, Interesting

      I am quite fammiliar with this effect myself.

      About 2 years ago I was turned on to "High definition" face shields for my motorcycle helmet. They have a yellow or pink tint to them. The Shoei ones
      being pink.

      WHat I noticed was it did cut down on glare and it was not obnoxious at night (just as the salesman had said, "sometimes I think I might be able to see something at nigh tbetter if I lift my sheild, and so I try it, and I never can see it any better")

      The thing was colors were so wrong.

      Now, 15k miles later, I put on the helmet and don't even notice that its tinted, my brain just instantly adjusts the color and I am off.

      -Steve

      --
      "I opened my eyes, and everything went dark again"
    3. Re:Check the links, editors by science_gone_bad · · Score: 3, Interesting

      "I still see red as red, green as green, blue as blue and white as white. At least my brain compensates for the difference in light temperature"

      Exactly!!! Incadesent lamps have lots of wavelengths. Florescent lights tend to be heavily weighted to UV due to the phosphor on the bulb and the fact that the gas inside them tends to have a more limited wavelength band. These actually created the light we see. But we don't see bluish objects around us, we see the color as we remember them to be!

      I saw an extreme example of this effect in SF at the Exploratorium. They had 2 street lamps one Sodium Vapor and one Mercury Vapor. The Sodium Vapor Lamp puts out only one wavelength of light (Sodium light is the most pure outside of a laser) while the Mecury Vapor lamp puts out lots-o-wavelengths i.e. White light.
      Since we see light being reflected from an object, we can only see the frequencies available to us. Looking at a picture illuminated by Sodium will ONLY produce a greyscale image as there's only one wavelength to see, but our minds will interperet the greys as color. Until you look at 1/2 the picuture in Sodium and 1/2 in the Mercury Vapor lamp. All of a sudden that colored picture turned into the pure greyscale that it really was.

      Now I cannot drive at night w/o thinking about that....keeps me properly freaked out!!

      --
      "I never get lost because everybody tells me where to go"
  2. Colorization is worth it by addie · · Score: 5, Interesting

    All of the spectacular Hubble images that have been released over the past few years have been composites of various grayscale images each falsely-colored by whatever elements or wavelengths they represent. The result is a truly spectacular image that is accessible to people who have no interest in what the images actually show, but in just the beauty of the image itself. The exact same thing is true of the Spirit images.

    We here on Slashdot rant about NASA budgets, and lack of interest in a manned space program. The only way to increase public interest is by catching their attention. Grayscale images simply are not going to cut it. I see no problem at all in colorizing images if it means more viewers are going to be interested, and therefore want to learn more.

    Sure, the purist in me finds it a bit irritating, but as with many things, the pros far outweigh the cons.

  3. To put the conspiracy theories to rest: by Delphix · · Score: 5, Interesting

    They're probably using a blue filter to block Raleigh scattering. We do a lot of image processing, and it's common to use a blue filter in images where you want sharp detail and aren't as concerned about the proper color. Blue light tends to scatter more because of it's low wavelength. If you don't filter it you can end up with just a haze in your image where you'd otherwise have sharp detail in the image.

    So put the conspiracy theory to rest.

  4. Re:Pictures are taken over time!! by Saven+Marek · · Score: 4, Interesting

    I live in an area where there are often dust storms for part of the year.

    That makes for a completely different light to that of a day overcast with clouds. generally clouds will completely remove distinct shadows, whereas red dust in the air will give an eerie dull appearance to the light, but keep much of the definition in shadows. Exactly like the mars image shows.

    The sky may look "overcasted" but anyone commenting that the cast from a dust storm is anything like that from an overcast cloudy day has rocks in their head. (martian or terran will do either way)

  5. What I'd like to see by suso · · Score: 5, Interesting

    What I want to see if Mars at night. Why can't they take a few pictures of what the two moons look like from the surface? They always take daytime pictures.

  6. Mosaic by drooling-dog · · Score: 4, Interesting

    I don't know about the colors, but one thing that I did find odd is the obvious and clumsy seams between the component images of the mosaics. I used to work with satellite imagery back in the early 80's, and it was pretty routine to resample the images so that they fit together seamlessly. I wonder why JPL isn't bothering to do that? It's not rocket science, after all...

  7. HST Images by cynicalmoose · · Score: 5, Interesting

    The .jpgs that NASA releases from the HST can't really be called 'false coloured' as they aren't the real data. Let me explain to those who don't spend their lives processing HST data.
    The data that comes off the HST is reserved for one year to the requesting individual/organisation (and, yes, this is controversial). But it is nothing like the images that NASA releases for the general public. The HST data comes down in a series of CCD output prints, often with whatever spectroscopy data has been requested, most often as a wavelength/intensity matrix. You can't dump that easily into any image editor; it's just a string of numbers. Equally if you dump all the spectra onto one image you will see a nearly black and white picture. So you select the spectra that interest you, and look for anomalies. The resulting pictures used are of little use to the non-astronomer - they aren't full colour, and are often just 4-bit colour showing intensity of a particular spectrum. The pretty pictures come from working out what looks good and combining it, so all images are 'false colour' in some way or another.

    I don't know about the Spirit mission, but I'd guess the same applied

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