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Post by alex04 on Jul 11, 2007 15:25:23 GMT -4
That's a great picture. I guess an HB could say the picture was taken with some sort of fish eye lens or something. But the again, all you would have to do is take a walk in the park to find that it's accurate. Which is what I'm going to do right now, and take a picture. There's actually a great example of a photo that i'm trying to find that has a run of wooden posts, and each shadow is on a different angle - it was posted by a guy that was debunking this part of the hoax theory on the abovetopsecret.com forum
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Bob B.
Bob the Excel Guru?
Posts: 3,072
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Post by Bob B. on Jul 11, 2007 15:42:34 GMT -4
There's actually a great example of a photo that i'm trying to find that has a run of wooden posts, and each shadow is on a different angle - it was posted by a guy that was debunking this part of the hoax theory on the abovetopsecret.com forum This one? The photographer has given me permission to use his photo on my web page.
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Post by alex04 on Jul 11, 2007 15:49:41 GMT -4
damn, spot on!
Is that a commonly used photo in debunking moonhoax arguments related to non-parallel shadows?
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Post by dexter on Jul 11, 2007 16:36:50 GMT -4
This is my favorite website when it comes to debunking Percy. It shows that all you need is a camera and an exploratory mind to see that Percy is full of sh*t. ;D
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Post by alex04 on Jul 11, 2007 16:38:58 GMT -4
forgive my ignorance, but who's Percy?
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Bob B.
Bob the Excel Guru?
Posts: 3,072
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Post by Bob B. on Jul 11, 2007 16:43:35 GMT -4
Is that a commonly used photo in debunking moonhoax arguments related to non-parallel shadows? Sean (I don't remember his user name) first posted that photo over at BAUT a few years ago right after he took it. I was in the process of updating my web page at the time and asked if I could use it since it was such a good example of non-parallel shadows. Aside from my page and BAUT, I'm not aware of any other common usage of it, though I don't visit too many other forums. EDIT: Sean's user name at BAUT is "AGN Fuel". He is the thread in which he first posted the photograph. For those who claim shadows must be parallel.....
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Bob B.
Bob the Excel Guru?
Posts: 3,072
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Post by Bob B. on Jul 11, 2007 16:48:34 GMT -4
This is my favorite website when it comes to debunking Percy. It shows that all you need is a camera and an exploratory mind to see that Percy is full of sh*t. ;D Yep, that’s a good web site. forgive my ignorance, but who's Percy? David Percy is a photographer and moon hoax promoter who has written a book and produced a video. Here is his web page: www.aulis.com/
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Post by PhantomWolf on Jul 11, 2007 17:22:02 GMT -4
Actually ANG's photo busts a number of HB myths.
First you have non-parallel shadows, but you also have an offset photographer's shadow, a slight brightening/halo effect about the photographer's head and finally you have the zero-phase shadow effect that makes the ground look a lot smoother and brighter than it actually is, all things that are found in Apollo photos and called anomalies. It just shows how few of those that claim to be photographers and photo analysts and find such "anomalies" actually go out, take photos of the real world, and then compare them to the Apollo record. If they did, they would find exactly the same anomalies in their own images.
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Post by JayUtah on Jul 11, 2007 19:23:51 GMT -4
Instead photographers like David Percy take sample photos that specifically exhibit the special cases where those effects are not as apparent, trying to pass them off as the general case.
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Post by nomuse on Jul 11, 2007 21:54:18 GMT -4
I was fairly convinced during the "length of shadows" argument that David Percy is not merely confused but in fact is actively duplicitous. Anyone who physically put a light source and camera in studio and worked to set up shots demonstrating the effect on shadows of movement towards or away from a light would of necessity discover the actual behavior. That he carefully frames his shot to use only the wall behind the subject, and attempts to conflate height of shadow with length of shadow, is evidence enough for me that he well understands the reality of the situation and is actively working to deceive.
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Post by JayUtah on Jul 12, 2007 0:18:24 GMT -4
Agreed. The sum of David Percy's behavior suggests to me he knows very well that he's wrong and doesn't care as long as the checks and accolades keep rolling in.
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Post by Kiwi on Jul 12, 2007 5:38:35 GMT -4
Back in March 2003, I queried David Percy on his Aulis message board about the non-parallel shadows in this photo and another on the same page in Dark Moon: On page 21 of Dark Moon it says: "Take a look at (19) and (19a), pictures of typical tree shadows [on page 22]. Notice the parallel lines of shadow..."
Yet if we very carefully lay straightedges along the centres of the tree-trunk shadows, we find that the shadows of (19) converge from the base of the trees, and they diverge in (19a), exactly as the rules of perspective state. In fact the vanishing point for each picture appears within the boundaries of the adjacent picture. This being the case, why is it claimed that the shadows are parallel?"Percy replied: Doug, apparently you do not understand the term 'vanishing point.' You back up this inaccuracy with the assumption that these two pictures were taken at the same place - which they were not. In fact the shadows of these tree trunks are lying in a virtually parallel direction. The branches of these trees seem to be misleading you…
AulisMy answer: Aulis: Thank you for your reply.
No, I am not confused about the tree branches, and having been a photographer since 1968, I have a fair understanding of how shadows cast by the sun (and any other parallel lines) converge to a vanishing point in a photograph if the viewpoint is not perpendicular to those shadows or lines. Lines drawn along the centres of the tree trunk shadows (not the branches) in (19) converge at the top of (19a), approximately 25mm from its right border.
Likewise, lines drawn along the shadows of the two large trees in (19a) converge at the top of picture (19), above the left side of the rightmost tree trunk. This must be done carefully, as there is only about 6mm of useable tree trunk shadow of the left-hand tree in (19a).
The proof is in the doing. Any owners of Dark Moon can do this exercise themselves and prove that the shadows of tree trunks are FAR from parallel as claimed.Aulis's reply: Doug, the key point is that in these tree examples the shadows are relatively parallel in comparison with the diverse shadows displayed within any one example of the Apollo photographs and within much of the TV coverage. We shall clarify this point in future editions.
AulisHmmm. "Lying in a virtually parallel direction" and "relatively parallel", yet he says on page 22: clearly it is simply not possible to have variations in shadow direction on flat terrain… within any one picture, if that photo is genuine (His emphasis.) Note Percy's earlier comment: "You back up this inaccuracy with the assumption that these two pictures were taken at the same place - which they were not." I neither assumed nor implied such a thing, and merely said, "In fact the vanishing point for each picture appears within the boundaries of the adjacent picture" because of the juxtaposition of the two photos on the page. Who was confused? At this particular time, JayUtah and another guy were asking some other curly questions and soon after Aulis closed down the message board. Whenever I hear people enthusing about Dark Moon, I encourage them to test Percy and Bennett's reliability by laying some straightedges along those shadows.
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Post by JayUtah on Jul 12, 2007 14:39:34 GMT -4
Percy replied: Doug, apparently you do not understand the term 'vanishing point. ...
David Percy's hubris on this point has always astonished me. It is the near-unanimous opinion of everyone I've consulted that Percy is, in fact, the one who does not understand vanishing points.
While I'm not nearly as experienced as Kiwi in photography, I have nevertheless observed the world quite extensively through a camera. In 2006 I produced around 6,000 photographs with one of my cameras alone. I can say with considerable empirical footing that shadows cast by the sun on natural terrain simply do not behave the way Percy says they should. Percy proposes to establish a rule that legitimate photos must obey, but he does not show where he validated that rule.
But it doesn't stop there.
I'm quite familiar with the mathematics of projection, having taught it at the college level. Not only can I produce a large volume of empirical evidence that fails to validate David Percy's expectations, I can explain in as theoretical a set of terms as is desirable exactly why the empirical data is the way it is and why Percy's expectations are deceptively naive. I can supply mathemtical proof for why a camera lens produces a convergence of shadows or any other parallel lines.
In fact, the true nature of projection as it affects shadows is quite different from what Percy expects. Percy identifies a shadow direction as that direction formed by the intersection of the caster with the receiver surface extending along the receiver following the visible shape of the shadow. Reasoning about projection by this method requires accounting for the affine geometry of the receiver. Percy asserts, but cannot prove, that the surface is perfectly flat in Apollo photographs. But in fact a valid and far less problematic method of reasoning about shadow vanishing points comes from the imaginary lines between features on the caster and their corresponding shadows on the receiver. Those are straight lines defined uniquely by two points on which must lie the light source in projective space. They are unaffected by object geometry or by camera position.
I have an extensive library. In it are books written in the 1930s and 1940s illustrating the art of geometric construction for rendering, the process taught to engineers and architects by which they can render photorealistic shadows manually by exploiting the well-founded mathematical principles above before CAD obviated the need. Shadow vanishing points are not the same vanishing points as apply to the actual geometry of the depicted objects. So the rendering of your ship's superstructure will use one set of vanishing points to correctly project the lines of the steel construction, and another completely different vanishing point to position the shadows correctly. Conceptual artist Ron Miller (Dune, 1984) has written an excellent essay on this that will appear in my book.
Also based on this mathematical foundation is the science of shadow vanishing point analysis, a standard tool in the photogrammetric repertoire of the qualified photographic analyst. Photographers do not normally study that. I believe it was Joe Durnavich who provided David Percy with SVPA studies of Apollo photographs Percy said were anomalous, as well as several synthetic examples validating the method. Percy predictably pooh-poohed the method as obfuscatory and unnecessary, but gave no argument relating to its correctness.
Further, Percy argued that SVPA could, at most, detect only when shadows were cast by the same light source. It could not identify that light source as the sun. Unfortunately such a claim of identification was never made, making his rebuttal a straw man. And Percy himself executed one of his deft changes of horse for which he is so justly infamous: his argument was that shadows such as those could be produced in true photography only by multiple light sources. Since the sun is a singular light source, any photograph showing evidence of multiple light sources cannot have been taken using only the sun as illumination.
With that presumption in tatters, Percy's argument fails. His ad hoc revision might have worked had he not embarked in Dark Moon upon one of his characteristic misplacements of rigor. He goes to great lengths to establish that no supplementary lighting was taken to the Moon, emphasizing that the basis of his argument was the alleged multiplicity of lights.
My testing shows that a single unfocused point-light placed farther than about 75 meters from the scene will produce shadows indistinguishable in photography from those cast by the sun. Wait! Gasp! Can't conspiracy theorists use that fact to argue that Apollo photography can be faked convincingly in the studio? Well, yes and no. Never hide from the facts, however disappointing they are. However, the lighting arranged thus will be accurate only in its depiction of shadow direction, not in all visible respects. Further, the important point is the undermining of the presumption that conclusive arguments on authenticity of photographs can be made by examining shadow direction. Thus arguments of the form, "The shadows are all wrong," are not in toto valid.
Doug, the key point is that in these tree examples the shadows are relatively parallel in comparison with the diverse shadows displayed within any one example of the Apollo photographs...
Another infamous change of horses. There is a dramatic difference between and argument that says true shadows must be exactly parallel and one that says true shadows can only converge to a certain extent. Convergence versus non-convergence is essentially qualitative while more or less convergence is quantitative. Percy does not provide a quantitative argument, and indeed seems to argue that a quantitative argument is obfuscatory and unnecessary.
So when faced with overwhelming empirical evidence that his expectations are unfounded, David Percy falls back to a position that isn't supported by his original line of reasoning. He changes the fundamental character of his argument, making it sound like a small concession.
At this particular time, JayUtah and another guy were asking some other curly questions and soon after Aulis closed down the message board.
After David Percy said that shadows in true photographs could diverge, but only by a small amount, I pointed out that his own sample photographs alleged to be true in a different context showed shadow divergence to the utmost.
Percy proposes a set of rules by which photos can be judged authentic. His first deals with the shadow directions, in which he asserted that sun-cast shadows must be exactly parallel. His tree photos are given in evidence of that. A subsequent rule argues that shaded sides of objects should invariably be dark. In connection with that claim he reproduces an artistic photograph of a cowboy silhouetted in the sun, hoping the reader will believe that's how all such photos would behave. Of course the light rays in that picture clearly go in every which direction, thoroughly demolishing Percy's claim that sun-cast rays can only slightly converge. Percy evidently didn't consider that photos intended to depict lighting levels might also depict shadows that violated his rules.
I asked for a reconciliation of his claims with his own example photographs. I didn't get it. Within a day or two the entire discussion board and its questions, claims, and counterclaims vanished without a trace. Not the first time this happened, either. A previous message board was shut down for "maintenance" for a period of months after the questions on it got a little too hot for the hosts to handle. But what's worse is that an article Percy wrote long after quoted one of my statements from that old message board. He kept the board contents so that he could selectively quote his critics.
Not only that, David Percy has declined two offers to defend his claims against my criticism in separate third-party productions. After the first aired, Percy disingenuously wrote an article on his website nit-picking some aspects of it. I find that most cowardly. Percy will discuss his claims only when he as absolute control over the presentation of the discussion. His behavior is that of a man running from the truth, not toward it.
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