Quote:
Originally Posted by Bad. Guardian
While browsing recently, I came across a number of angry web pages which argued that a certain image of the "face" on Mars, in a certain JPL press release, was a fraud. To me, personally, the "face" has always seemed to be an accident of nature.
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Are you referring to the so-called
"catbox" image?
Quote:
Originally Posted by Bad. Guardian
But when I encountered this controversy a few days ago, I saw it as an opportunity for a fascinating mathematical challenge: an attempt to determine the exact algorithm that was used to "flatten" the landform in the image. I tried some Fourier tricks, and succeeded. The algorithm is a very simple 1x31 convolution, which resembles a crude and grossly exaggerated unsharp mask. It produces all of the expected effects: it eliminates vertical streaks, and and gives the surrounding flat land a "grainy" texture, and creates "false shadows" above and below a small bright feature near the east edge of the image
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What is the basis for stating that the image was "flattened" (other than "angry web pages")? It does not look flattened to me.
Eliminating artefacts like vertical streaks is why images are processed. Is this bad?
Whaat is the evidence that "real 3D" shading cues have been destroyed and "false" shading cues and shadows created?
Whaat evidence you you have that the surrounding flat land has been given a "grainy" texture?
Are you aware that this image, taken under poor conditions (off axis, and with haze and cloud) still show much more detail than the best Viking image?
Quote:
Originally Posted by Bad. Guardian
I experimented with similar convolution kernels in varying sizes, and it does indeed seem that the size 1x31 is particularly well suited to the purpose of deceiving the viewer about the true 3D shape of this particular hill.
Was the deception deliberate, or accidental? I don't know.
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Whaat is your evidence that there has been any deception at all? The processing of this image is a matter of
public record.
Quote:
Originally Posted by Bad. Guardian
If the people who issued the press release were fooled by their own deceptive image processing, and really believed that the "face" was not actually a hill, as it appeared in the Viking images, but instead was a jumble of boulders encircled by a trough, as it appeared in their press release image, then their mistake was an honest mistake. But even if they were honestly ignorant of the problem, they could not have remained ignorant for long. Tim J. Parker's enhancement was released that same day, and anyone who looked at both images could see that the processing of the original image had been deceptive-- so deceptive, in fact, that it could reasonably be expected to inspire conspiracy theories.
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What is your evidence that the people who issued the press released were fooled?
What is your evidence that they did not think it was a hill, but a "jumble of boulders surrounded by a trough"? To the contrary, MSS have repeatedly called it a hill.
Tim Parker's
image looks a bit different because it was processed slightly differently. This is normal. The features in both images are the same.
Quote:
Originally Posted by Bad. Guardian
The right thing to do, at that point, would have been to issue another press release, retracting the bogus image, and apologizing for the mistake. Someone decided not to do the right thing. This, then, would be two individual acts of Bad Astronomy: first, the original, possibly accidental, use of bogus data in a press release; second, the decision to refrain from issuing an apology and retraction, when they learned that an image in their press release was bogus.
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So far you have not shown any evidence that the MSSS release was bogus. So there is no need for apology and retraction.
Jon