posted on Apr, 6 2008 @ 12:27 AM
Originally posted by Blaine91555
This color thing is a red-herring. NASA always labels its photo's as to whether they are true color or not.
I shoot photo's in a Raw format which means I have to correct the color of the photo's I take here on earth just like they do the photo's from
Since I have an ambient light sensor sitting on my desk from Datacolor, I'm fairly sure they included a similar device on the Rovers. With that
information and the RGB Channels they could get really close to what you would see on Mars. With all that iron oxide in the dust, the amount of dust
in the air and the time of day could dramatically alter the colors at different times of day; just like sunrise and sunset on earth. The overhead sky
may well appear blueish at high noon but very red earlier and later in the day depending on the angle of the sun.
For me to get accurate colors here on Earth I have to constantly calibrate my monitor, scanners and printers with color profiles created with special
sensors. With point and shoot digitals you are just getting approximations based the the histogram. Thats why you have different choices of setting
for daylight, cloudy and so forth on most digital cameras. To get the real colors you have to use a target to get the white level before you shoot and
make sure your color profiles are right for your printer. Even then it is just a good approximation.
When the first picture of mars was taken and reconstructed back on earth, everyone thought mars had a blue sky. The filtering errors between the data
being gathered, and the data being reconstructed caused many to think that mars had a blue sky at first (like earth). They later learned that wasn't
the case at all (supposedly).
One thing scientists learned was that Mars' sky was pinkish in color, not dark blue as they originally thought (the sky is pink due to sunlight
reflecting off the reddish dust particles in the thin atmosphere).
From Spherix.com abstract paper by Ron L. Levin and Gilbert V. Levin, paper entitled "Solving the color calibration problem of Martian lander
The first color image (12A006/001) of the surface of Mars was taken July 21, 1976, at the Viking 1 site, one day after the landing. Immediately
displayed on color monitors at JPL, as seen in Figure 1a, the landscape awed observers with its resemblance to that of Arizona. Typical desert
colorations of soil and rock, ranging from umber sand to yellowish-brown and olivine-colored rocks stood out clearly under a blue sky. Two hours
later, however, the official image was changed to the monotone of orange-red (NASA P-17164), Figure 1b, that, with few exceptions, has prevailed in
NASA-published images of Mars ever since, as presented by Mutch et al.. However, a spectral analysis of color images of the Viking 1 site
reported a broader palate. The paper made the first, and perhaps only, reported use of JPL’s Image Processing Laboratory to analyze digitally
the red, green and blue color channels of the images taken by the Viking 1 lander camera. In addition to studying the color images, their RGB
components were transformed into saturation, hue and intensity components to enhance subtle deviations. When these components were equally amplified
to produce an equal average sensitivity over the spectral bandpass, the resulting “radiometric” (closest possible approach in appearance to a
human observer) images very closely resembled the first color image (12A006/001). Among the range of colors, the paper reported that some of the
rocks exhibited greenish patterns that apparently changed between images taken 301 sols apart. Radiometric images of lichen-bearing terrestrial rocks
taken and processed through the same system as were the Viking images showed a close resemblance of the lichen colonies to the greenish patches on the
Mars rocks. Inclusion in the analysis of three near-IR channels available on the Martian images enhanced the greenness of the patches that were, to
the sensitivity of the method, virtually indistinguishable from the lichen colonies on the terrestrial rocks.
Some believe that the first mars image to be sent back to earth was the accurate color of mars, not the reddish hues which we are all so accustomed to
being shown. Nasa hasn't exactly been honest about UFO's in orbit even though many of the UFO events have occured on live TV broadcasts, and nasa
astronauts have actually called objects in orbit UFO's before on TV. How can we honestly say they are being completely honest about this? Food for
[edit on 6-4-2008 by BlasteR]