__________________
Never attribute to malice what can be adequately explained by ignorance or stupidity.
Isaac Asimov

__________________
Never attribute to malice what can be adequately explained by ignorance or stupidity.
Isaac Asimov

man on the moon, thank you for that valuable contribution. You've provided a new, and very useful, way to explain the problem.

I've been considering Dr. Plait's comment that the image had very little "faciness," even before it was badly processed. I think that that comment has led me to a better understanding of the original grievance.

You may remember that I mentioned that I was introduced to this image by "a number of angry web pages." I now think that the anger probably wasn't particularly about the "face" itself, but instead was mainly about the "platform" on which the "face" seems to rest.

The "platform" is fairly level and smooth and regular, and it exhibits extremely curious symmetry. Even though I consider the entire landform to be an accident of nature, I have to admit that if someone had shown me a picture of a terrestrial mesa with that particular shape, I probably would've said something like this: "Sure looks man-made to me. I bet a dig would turn up artifacts."

Now, back to your topo map analogy. As I said above, it's very helpful. Try looking at the "catbox" problem this way: The image that was returned by the spacecraft looks like a _photograph_ of a platform-shaped landform, but the image that was used in the press release looks more like a _topo_ _map_ of a platform-shaped landform.

As you explained above, many people can easily get the wrong idea about the shape of a landform, when they look at a topo map. Imagine how much easier it would be for them to get the wrong idea, if you were to actually tell them that the picture is _not_ a topo map, but instead is an aerial photograph!

If you'll forgive some pure speculation, here's my rendition of the thoughts that might have gone through the mind of a hypothetical artificiality believer, when first confronted with the "catbox" image:

No, that isn't a conspiracy claim. Like Dr. Plait, I have no idea what they were thinking when they did the processing. I don't know whether it was accidental or deliberate.

But I do suspect that a bad decision must have been made, a day or two later. If you'll forgive some pure speculation, here's one possible version of the discussion that might have taken place:

No, nothing veiled. It's just what it looks like: a hypothetical question that I hoped would start a discussion about the question of whether it could ever be OK to fight Bad Astronomy with more Bad Astronomy. Jerry and Dr. Plait gave very good answers.

You're welcome.

Shading is something we're used to in great amounts when we're trying to look for relief, but it's easily overlooked because it's not in the forefront of our consciesness. When it's removed it can cause no end of frustrations. If it weren't a difficulty I encountered on a regular basis it probably wouldn't have crossed my mind either, so no worries. It's an analogy (I think you said that), I wouldn't recommend telling people has topo maps of Mars . What a riot that would be!

And don't kick yourself too hard . Keep working on answers. If you can do that...well, you'll go a long way.

Welcome to the board, btw, if you're planning to stick around. You may want to watch how you frame questions/approach people, but asking is never a bad thing. Nor is commenting if you've something potentially contributable.

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None to speak of

I've always thought the original 'face' was likely processed in a way that made it look 'the most human' to spawn interest; and whether or not that is true, I think the entire scientific community is rather chagrin that a major conspiracy theory was launched from such a trivial platform.

If you have followed the Cassini mission at all, you know that raw images are being quickly processed by amatures, and occasionally a jpeg, cosmic ray, or lens blot is highlighted as an artifact. This happens to the professionals as well - so while the original release may have overplayed the topography, I don't feel it is necessary to issue a retraction every time an image is poorly processed. It is reasonable to process the image in a way that highlights the topography to make the point that this is not Easter Island; just as it is reasonable to sharpen or blur boundaries when trying to knit an image of an entire moon from several passes. The alternative: Sitting on data until it is perfect, would mean images are rarely released in a timely manner.

If this were hard data there should be a retraction; but raw and processed images should always be taken with a grain of salt...especially when the an alien face pops out.

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jwj

It's ok not to know.

man on the moon, thank you for welcoming me.

One of the reasons why I chose this forum (aside from the obvious connection between badly processed images, and Bad Astronomy) was a desire to face well-reasoned objections, if any could be found. Aside from all the time wasted by basic confusion (which probably would have happened anywhere on the Internet) this has been mostly a good experience so far.

My only real frustration in this discussion is the fact that so many have continued to refer to the selective suppression of shading as a "claim," which seems to mean that they haven't been able to see the effect with their own eyes, even after I attached before-after-slope.gif. I don't understand how anyone could look at that animation and still be unable to see that the 3D shading of the slope has been suppressed, while the 3D shading of the small lump or boulder has been enhanced.

I'm attaching a new image which may be able to help those who have been unable to see the effect, even when they look at before-after-slope.gif. The two frames in this new image are the power spectra (*) of the corresponding frames in before-after.gif. The left frame is from the image that was returned by the spacecraft; the right frame is from the image that was used in the press release.

Can everyone see that the pixels of "snow" have been substantially darkened, in a well-defined band, across the middle of the power spectrum? The fact that pixels in the power spectrum have been darkened means that brightness variations have been _suppressed_. The fact that the darkening in the power spectrum has been mostly confined to a well-defined region means that the suppression was _selective_. The fact that the darkened region is in the middle of the power spectrum means that the _large-scale_ brightness variations are the ones that were selectively suppressed.

Can everyone see it now?

I also want to correct another misconception which seems to be very common here: the idea that the raw image needed some kind of difficult, time-consuming labor-- that it needed to be "carefully calibrated" or "highly processed"-- before it could be understood by normal human viewers. This is completely untrue. Only extremely minimal processing is needed: left/right flip, streak removal, and contrast normalization. My first script only took about ten minutes to write, using 1970s and 1980s technology (Unix shell and NetPBM). I didn't save it, but it was something like this:

Try it yourself, if you have NetPBM; the result is quite decent.

I just ran the above script on a low-end PC from 1997. Total run time was 2 minutes, 11 seconds-- and that's for processing the whole swath, not just the part with the "face." If I can do it in minutes with freeware and a low-end 1997 PC, then surely a professional with high-end 1998 software and hardware also could have done it in minutes, or possibly in seconds.

(*) power spectrum: each pixel depicts the logarithm of the modulus of the corresponding coefficient of the discrete Fourier transform of the image, shifted to place the wavelength=infinity coefficient as close as possible to the center of the power spectrum.

Attached Images

power-spectra.gif (115.4 KB, 11 views)

If you are prepared to come here and state, as fact, that Cydonia images were selectively edited to reduce the apparent 'faciness' of it - then you've got some serious questions to answer

1) Why subdue such an image when later images, better images, high resolution images, were always going to be taken, transmitted and released at some point in the future (i.e. HiRISE etc)

2) Why release an unsubdued image just a few hours later

3) Why release the raw image first (which anyone could process themselves) and THEN release an image intentionally processed to subdue details.

4) Why - why do it at all? For what purpose, directed by whom?

What you are inferring by your line of argument is a massive conspiracy of cover up and suppression....only a few hours later to throw it all away.

You yourself gave a link to a page which I have since quoted in this thread, describing the processing done to the very image you claim was intentionally edited to 'deface' it (if you'll excuse the pun). Are you saying that that page is a lie and that something else was done other than what was described

With Post 15, I see no reason why this thread shouldn't be moved to Conspiracy Theory, as that's what's being alleged and discussed.

You say:

Yet, you follow that with:

If that is what you are suggesting, that is a conspiracy.

Conspiracy: the act of conspiring together
Conspire: to join in a secret agreement to do ... (a) wrongful act ...

On that basis, I am moving this thread. Convince me otherwise.

__________________
Never attribute to malice what can be adequately explained by ignorance or stupidity.
Isaac Asimov

Hi Bad Guardian,

I'm at loss what you're driving at: do you believe that Phil Plait is personally responsible for a picure you claim has been fabricated or is this a discussion about a method you discovered how to fabricate desired results in images?

First, let me remind you that the Viking missions took place late in 1976 whereas Phil Plait got a PhD in 1994 - which makes a mismatch of almost twenty years to spin pics.

Second, during my university time (yes, I'm a rocket scientist and no I'm not with NASA) in the early eighties I had the opportunity to listen to lecture of a european astrophisicist by the name of Rudolf Kippenhahn. His topic was the Viking mission and the "face on Mars" issue was raised. He gave the following explanation, why the photograph resembled a face: the software which got the Viking data was instructed to paint any pixel that was garbled with a black dot. One of the dots happened to be at a nostril. When replacing this (which was exactly what some fellow students and me tried after the lecture) with a pixel coloured just the same as adjacent pixels the impression of a face is strongly weakened.
You see, even without your alleged "forgeries" it is much to the eye of the beholder and you don't need Photoshop to support wild claims.

Do you have any facts supporting your idea or is it onyl inference from your method? E.g. I found a way to emulate the same results hence NASA must have faked it.

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Any sufficiently advanced technology is indistinguishable from magic - Arthur C. Clarke

So it was really a molehill?

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Measure once. Cut twice. Power tools are fun.

Doug, I've already corrected that misrepresentation of my position, several times.

I _do_ state, as fact, that the large-scale variations in brightness were selectively suppressed. It's indisputable. You can see it yourself, easily, in the power spectrum. Have you looked at the power spectra in the message to which you're replying? Can you see the well-defined dark band across the middle of the second power spectrum?

I do _not_ use the word "edited," because it isn't the right word. As I explained in the first post in this thread, a very simple image processing algorithm, a certain 1x31 convolution, was responsible for the selective suppression of large-scale variations in brightness. The word "edit" isn't really appropriate for such a simple algorithm. It isn't appropriate to call the "string-lowercase" function a text editor; for the same reason, it isn't appropriate to call a 1x31 convolution an image editor.

I do _not_ state that the convolution was applied "in order to" change the appearance of the landform. As I've explained many times, I don't know why it was done. It may well have been an accident. You're the one who's been trying to turn this into a conspiracy discussion, not me. Please stop misquoting me.

I answered this question, days ago, when Jon asked it. Haven't you even read the discussion? See the message dated 24-December-2007, 02:46 AM UTC, titled "You need to understand which image is which."

Hi Extracelestial, welcome to the discussion.

No, the picture wasn't what I would call "fabricated." It was processed, with a certain 1x31 convolution, and the result of that convolution was deceptive. Before the convolution was applied, the image looked like a lumpy hill sitting on a platform-shaped mesa. After the convolution was applied, the image looked like a lumpy hill sitting on flat ground, with no mesa.

Apparently the photograph was taken, and the press release was issued, mainly because of a controversy among non-scientists. Apparently the 3D shape of the "platform" was part of that controversy. Therefore, the use of a convolution that "flattened the platform" was Bad Astronomy.

And no, of course I don't believe that Dr. Plait is responsible. I addressed the question to him, because he's the world's leading critic of Bad Astronomy. When you want to discuss Bad Fashion, you go to Mr. Blackwell. When you want to discuss Bad Astronomy, you go to Dr. Plait.

We're discussing a picture that was taken on April 5 1998, and processed the next day. The 1976 pictures aren't really involved in this discussion, except for the fact that a good look at those old pictures could have helped the person who applied the convolution, to understand that there really is a "platform" shape there, and to understand that the use of the convolution had caused the picture to misrepresent that "platform" shape, and to decide not to release the badly processed image. Unfortunately that didn't happen.

A rocket scientist? Excellent. Do you understand harmonic analysis, discrete Fourier transforms, power spectra, etc.? I'm afraid that no one else here understands this stuff. Except Dr. Plait, and I'm not sure he's still reading. Have you read the message that I posted yesterday, about the power spectra of the image, before and after it was processed? Can you see, and understand, the indication of selective suppression of large-scale variations in brightness?

Yes! Another example of a deceptively processed, widely publicized image... of the very same landform!

But there's a very important difference. The 1976 "dotting of the nostril" was officially acknowledged as an accident, immediately. As far as I know, the 1998 "flattening of the platform" has never been officially acknowledged as an accident.

If the converse had happened-- if the 1998 "flattening" had been acknowledged as an accident, but the 1976 "dotting" hadn't been acknowledged-- then I'd be deriding the 1976 incident as Bad Astronomy. But in reality, it happened the other way around... so I'm deriding the 1998 incident as Bad Astronomy.

No, I wouldn't use the word "forgery."

Which claim do you think is wild? I'd be happy to discuss any and/or all claims with you, especially since you're a rocket scientist. Have you read the entire discussion?

You can see the evidence in the power spectrum, if you know enough math to understand it. As a rocket scientist, perhaps you do.

If you look closely you'll see more than one band of darkened pixels. There are several bands, all horizontal, at regularly spaced intervals. The central band is the strongest, by far, and the other bands get progressively weaker as you move upward or downward.

Do you recognize this phenomenon? It's called "ringing." It's what you get when you fail to design your convolution as a nice smooth Gaussian, and instead design it as a simple rectangular pulse, with sharp discontinuities at the boundaries. The distance between the bands in the power spectrum indicates that the discontinuities in the convolution (the "edges" of the rectangular pulse) were exactly 31 pixels apart.

If the convolution had been Gaussian, instead of rectangular, then you wouldn't see all those other bands. If the convolution had been any other size, other than 31 pixels, then those bands would be separated from each other by a different amount of distance.

Do you see it? Do you understand it?

Even if you don't understand Fourier analysis, I'm sure that you must know someone who does understand it, since you're a rocket scientist. Show him or her the power spectra that I'm attaching to this message. Ask him/her if the change in the power spectrum does, or doesn't, indicate that large-scale brightness variations were selectively suppressed. Ask him/her if he/she sees "ringing" in the power spectrum. Ask him/her if this kind of "ringing" is caused by failure to use a Gaussian convolution.

You don't need to show him/her the original image; you can just show him/her the power spectra.

Trust me: everything here is very simple and obvious and straightforward, to anyone who knows enough math.

Or don't trust me (after all, why should you?) and show the power spectra to someone whom you do trust, and who knows enough math.
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Note: because of the forum server's attachment size limit, I've omitted the left 1/4 of each power spectrum. This isn't destructive, because of the inherent symmetry of power spectra of real images.

Attached Images

	before-ps-crop.png (131.8 KB, 4 views)
	after-ps-crop.png (134.2 KB, 5 views)

Jim, I don't believe that the hypothetical conversation that I posted would qualify as a conspiracy.

Doesn't "conspiracy" mean something that's planned in advance, rather than just a mistake?

In that hypothetical conversation, "Larry" did his job badly, and, a day or two later, his boss decided not to publicize the fact that "Larry" had done his job badly.

That's a bad decision, but it isn't a conspiracy.

Do you disagree?

It does almost seem that a couple of the participants here have been _trying_ to turn this into a conspiracy discussion, but I would argue that they haven't succeeded in doing that, because every time they've falsely attributed a conspiracy claim to me, I've immediately corrected them. It's been quite a challenge, trying to keep these people from turning this into a conspiracy discussion, but I do believe that I've succeeded... so far.

The only message here that could possibly be interpreted as an actual conspiracy claim is the message dated 22-December-2007, 05:08 PM UTC, posted by djellison, in which he indicated that the image called "raw" on the NSSDC web site is actually not even close to raw, but instead has been subjected to "careful calibration and processing." But he hasn't made any further attempt to "push" that claim. I asked him to clarify it, in the very next message, and he never answered. Probably he never really intended to make that claim; I think he was just confused.

In summary, there hasn't really been _any_ serious discussion of conspiracy on this thread. Just a handful of attempts to misrepresent my statements, which were immediately corrected, and a single random accusation against NASA's raw image, which was probably just confusion.

Have I convinced you?