| Rebuttal of Ace Baker's "Chopper 5 Composite" Analysis
29 July 2007 UPDATE: Second Rebuttal, 3 August 2007 UPDATE: Addendum, 6 September 2007 UPDATE: Critical Review of Fox 5 Video Fakery Claims, a summarized and updated version of this page, 6 September 2007 Many times in the past several years we've seen dramatic claims before of a physical proof of no-plane claims. These previous false-alarms have been exposed as incompetent and amateurish mistakes and Ace Baker's analysis of the velocities of the plane in the Fox 5 footage is no exception to this pattern. Baker claims that the much lower margin of error in the measurements of the plane's speed in his control cases, shot on DV video, prove that the motion of the plane in the Fox 5 footage is unnatural. This claim is in error. The control cases are not equivalent to the Fox 5 footage and do not shed light on the expected margin of error in the Fox 5 analysis. In fact, his control footage is sharper and lacks the noise and distortion (visible in the wavy, rippled edge of the WTC towers) of the VHS source for the Fox footage. Apparently Baker does not have much experience with motion tracking/stabilization, or else he would have realized that the success of the process depends on the clarity of detail of the tracked object and the consistency of that detail from frame to frame and not so much on the number of pixels that object occupies. It's not at all surprising that he achieved a lower error rate with his control footage analysis. Additionally, the fact that the velocity curves for before and after the stabilization of the Fox 5 footage are roughly the same is exactly what we would expect: stabilization of the Fox footage would not change the variations in speed, except for some jitter caused by the software stabilization process (which can be seen in the higher errors in Baker's stabilized velocity graph). The helicopter had a mechanically stabilized camera system to remove shakes and vibration, leaving only a steady drift to the left, probably caused by the helicopters movement. Stabilizing this footage removes the same amount of movement from each frame, leaving the before and after measured motion variations the same. So the only question remaining is: do these variations exceed what would be the expected margin of error in measurement of the Fox 5 footage? For this an attempt to calculate that error must be made. The subjective placement of the wireframe over the plane image is definitely going to create some error. The following diagram shows 3 possible placements (at 800% magnification) of the wireframe over the image, one in a center position and two other positions moved to the left and right .5 pixel. The size of the pixels can be readily seen.
The center and left positioning are virtually indistinguishable, and the right adjustment only barely looks out of alignment. So the exercise of visual placement alone introduces a minimum margin of error of just less than 1 pixel. And there are more factors which would add to the margin of error: Given the error in visual placement plus these other two factors, the margin of error should be at least 1 pixel and could possibly be higher. A velocity measurement uses two position measurements, therefore the minimum margin of error in the velocity measurement would be 2 pixels or higher. The following shows the stabilized footage with a wireframe overlay placed over the plane and a timeline showing the change in position and speed of that overlay: http://www.questionsquestions.net/WTC/fox5velocity.html Frames 12 and 13 were excluded from the velocity calculations because the plane behind the graphic. Frames 1, 11, 14 and 22 are probably unreliable because not enough of was not sufficiently visible to make a reasonably reliable position measurement, in my opinion. However, I used them anyway. Now, if the plane is real and moving smoothly, the difference between two velocity measurements should not exceed 2 pixels. This is exactly what is the case, as shown in this graph of the velocity of the wireframe:
The largest change in speed between any consecutive frames is between frames 2 and 3, 6 and 7, and 18 and 19: a 1.6 pixels/frame change, which is less than the 2 pixels/frame minimum margin of error (corresponding to a .8 pixel error in position, which could be accounted for by the subjective error in positioning alone). Thus, the motion of the plane in the Fox 5 footage clearly matches the smooth, natural motion expected of a real plane. Baker's measurements of larger errors are simply not representative of the Fox5 footage, and are a result of less accurate placement and stabilization. (By the way, Baker apparently doubled the image size of the 640x480 footage before measurement, resulting in motion of 20-25 pixels per second instead of around 11-12. His values must be multiplied by .56 to be equivalent to the values in my graph above, which come from the 720x480 footage at normal scale). One might argue that Baker couldn't have come up with such similar graphs of velocity for the stabilized and non-stabilized versions of the Fox footage unless those variations were authentic, but this would not be necessarily true: he could have simply made the same subjective errors in positioning the wireframe both times, resulting in similar graphs. In regard to the exit of the plane, the alleged "nose cone" emerging from the building is not the shape of the nose of the plane: it is very clearly thinner than the nose of the airplane when it first exits the building, then grows in size to approximate the shape of the nose, then continues to widen and starts to move down a bit, which is exactly the behavior one would expect from a smaller piece (or pieces) of debris pulling an expanding cloud of dust or smoke behind it. It simply can't be part of a keyed plane image or CGI model. Furthermore, because the shape is changing Baker's motion tracking data of its velocity is meaningless (and also mostly within the margin of error anyway). So in summary: •Baker's control cases are not equivalent to the Fox 5 footage and don't contribute anything to the calculation of a margin of error There's really no need to read further or to revisit this issue in the future. But I have some more observations for those who want to explore more, for in addition to the technical mistakes Baker's article is a perfect example of biased and illogical thinking masquerading as a serious, scholarly work. Baker's arguments show that he doesn't understand how keying and compositing is achieved on a professional level. His idea that footage of a real plane was chroma keyed live is absolutely silly. It would never be used when photo realistic CGI would better accomplish the task (unless the perps deliberately wanted to emulate 1950's quality special effects and expose themselves). The only exception would be when both pieces of footage are shot using the same motion control camera movement, which would match the motion of each perfectly and eliminate motion anomalies of the type he says can be observed (and which aren't there anyway). And if they did use live footage, it would not be keyed live but be prepared ahead of time with keying and/or rotoscoping to create a clean image digitally formatted with an alpha channel, and they could have easily fixed any variations in movement at that time. Besides, in broadcast video, the "Sportsvision" technology he says was used to sync the footage is used with CGI images, not chroma keyed footage. Not only could CGI be perfectly synced to the motion of the background footage, it could be cleanly overlaid, eliminating the problems with edge details that go along with chroma keying. On that subject, the pink-colored artifacts he mislabels "digital paint" could be a result of keying of real life footage, but that would not have been done, as explained above. These are artifacts are noise resulting from broadcast transmission, poor quality VHS recording or compression. Like all the other no-plane arguments, there are fatal logical flaws to the scenario Baker argues. If an overlay was used, the Fox 5 footage shows that the overlay was perfectly synced with the WTC towers: jets of dust come out of building exactly where and when the plane hits (propelled by last second operation of jet engines, as seen in the Fairbanks footage). This tells us that the overlay of the plane would have been placed exactly where the alleged planted explosives would have been in the building, confirmed again by the flames coming out directly opposite on the other side of the building a split second later. So the timing and positioning of overlay would have been precisely coordinated. Therefore (since they would have used CGI and nothing else) it doesn't make sense that there would be any irregular movement of the overlay as Baker suggests. And it also follows that it doesn't make any sense at all to suggest that the conspirators would mess up the exit of the model from the building when the entry was absolutely perfect, AND furthermore to suggest that they remembered to slow down the overlay during it's penetration of the building (as seen in Baker's velocity graphs) yet forgot to have it actually stop within the building. It seems that no-planers simply can't think logically. Baker suggests that clear weather was essential to the conspirators plan (because of their rather unprofessional plan to use chroma key). And just how did they ensure clear weather for a date planned months in advance? Was God in on the plot? Amazingly, this is even more idiotic than the previous no-planer assumption that the conspirators could have controlled all the cameras in New York on 9/11. I've used the term "fools rush in" before and it certainly applies to Baker's substanceless article which is filled with technical analyses that are beyond his level of experience. In addition to the bogus technical claims, he cites a series of no-plane arguments (such as that the plane in the Naudet footage can't be a 767) which not only have already been thoroughly debunked (and a long time ago too) but which were debunked with analyses much simpler than the kind he himself attempts in his article. Since he has demonstrated himself perfectly capable of understanding these other simpler arguments, one can only assume he possesses not only a pathological level of intellectual dishonesty, but a zealous bias towards the no-plane scenario totally in contradiction to the scholarly tone of his article. But as we already know, the no-plane argument has only been sustained through distortions and lies, so this is not surprising. I felt obliged to revisit this issue and conduct this analysis, since this analysis is outside the experience of other 9/11 researchers I know who are working in this area.. Unfortunately it was a royal waste of time, delivering totally predictable results. The lack of a logical scenario for the no-plane theory should be enough, but many people don't think logically and, sadly, propaganda like this still has to be rebutted, as the unwary will be suckered in by it's veneer of authenticity. Rebuttal to Ace Baker's "Deconstruction of Eric Salter's Chopper 5 Rebuttal" Baker's response to my article contains continued technical misunderstandings and rather ill-considered attempts to cast doubt and suspicion on my methods and motives. He said:
No, I actually based my paper on the fact that the motion of the plane in the stabilized footage is smooth and natural, showing no more than a .8 pixel variation in position. Once the footage is properly stabilized, it doesn't matter whether there were shakes or not, only whether the plane's motion is smooth or not. When the camera motion is eliminated the only other irregular movement should be from the supposedly errant overlay. Baker seems not to be able to understand this concept, which is rather basic.
Baker just can't accept the fact that his DV control case is sharper than the VHS Fox footage, something that experienced editors can see right away but evidently he cannot. His control cases are bogus, yet he insists on continuing to use the error values he gleaned from them. I showed conclusively that the subjective error in positioning the wireframe on the Fox footage would be a bit less than 1 pixel. Baker is just embarrassing himself by calling that figure "huge." And remember that all of my position measurements are at or below this error. I did misunderstand the method Baker used to calculate the non-stabilized measurements, but that is irrelevant. The key issue is that I showed that the motion in the stabilized footage is smooth and regular.
I concealed nothing. Knowing the numerical change in the position values is necessary for Baker's methods, not mine. That the results of my stabilization are reliable can be seen in the regularity of the position of the side of the building in my stabilized footage. And contrary to his charge of "tampering" selectively with individual frames in stabilizing the footage, I checked every frame in relation to a reference frame while making manual alignments, the same method he used. Someone objecting to my results only has recourse to finding errors in the stabilizing of the footage or the placement of the wireframe overlay, which Baker and I both did visually. In fact, the positionings I made could be adjusted to be make the velocity data either more or even less variable than what I achieved and still look acceptable visually. Because of this subjectivity, the analysis of this footage will never be more than contested and it will never amount to conclusive evidence of video fakery, which makes future analysis of this footage totally meaningless. No doubt Baker wants to fiddle with this until he finds more variation than I did, but that would be an exercise in futility. Furthermore... Even if the footage could be proven to be fake, it would only be evidence for fake footage (albeit with the twist that it was done live and with the help of a news copter crew). It would not constitute support for the WTC no-plane theory, which remains baseless. It's interesting that Baker continues to insist the "nose" has to be part of an overlay even though it's clearly not the shape of the plane's nose and changes shape. This is what I referred to as zealous bias, although maybe it's better described as willful denial. And even if there is uneven motion in the "nose" it could be explained as variations in air pressure pushing out a cloud of smoke or dust. His scenario of pre-prepared real footage overlaid live with an alpha channel is illogical, since any motion variations in that footage could and would have been removed (stabilization). And that corrected footage would then be matched to any shakes in the helicopter camera by the Sportsvision technology, avoiding any motion errors. That's the whole point of that equipment. He seems to have forgotten this fact after mentioning Sportsvision in his article. Is this just confusion? And for extra credit, let's look at Baker's description of motion tracking:
Uh, calculating overall position is not a factor of the tracking process but what tracking does.
No, the geometric center is not tracked. LOL! The tracker recognizes details (brightness and color data) in the image and tracks those details from frame to frame, giving the position of the tracking region defined by the operator, not the geometric center of the object.
No, Baker has it backwards and has shown not only technical incompetence, but also quite a bit of presumptuous arrogance. That's what leads to biased, erroneous results. The above page has been summarized and updated in a new article "Critical Review of Fox 5 Video Fakery Claims" The DV movie file of the Fox 5 VHS footage is posted: Two more DV movies from the dub of the VHS tape of live 9/11 coverage have been uploaded. These were replays, since Fox 11 was being recorded when the 2nd hit occured live. Baker, in his response to my article, makes a big deal about needing my After Effects project to see data that I "concealed". So let's examine his methods. When writing my original critique, I thought Baker had measured the positions of the plane twice, in the stabilized and non-stabilized versions of the video. But this is the method he used to synthesize the non-stabilized position data: My non-stabilized data was derived by starting with the stabilized data, and subtracting the distance each frame had been moved from the previous frame in order to stabilize it First of all, this method is unnecessary: From a fixed vantage point, a real plane would not have measurable variations in the speed from frame to frame-just 1/30th of a second (at least not measurable by this tracking method for a plane travelling through air). Stabilizing the footage creates that fixed point of reference, so all you need to do is determine whether the plane's motion at that point is smooth (variations not exceeding the margin of error). There are only 2 issues to address: Secondly, the Fox 5 footage already had mechanical stabilization on the camera, which resulted in the only motion being a smooth pan to the left, with the exception of slight bump in frames 12 and 13 of the clip Baker used. Therefore, the stabilized and non-stabilized velocity graphs should have mostly identical contours. This means that the differences we see in those two graphs could be caused by the positioning errors in the stabilization and tracking that Baker did. Depending on the offset of the position errors, the non-stabilized graph could have more, less or the same amount of variability as the stabilized graph, and examples of all three can be seen in Baker's graph. Baker just assumes that the difference in the data sets is due to unusual motion in the plane and not his positioning errors, which is not good science. In the end, Baker's exercise is both unnecessary and psuedo-scientific, as well as potentially misleading. However, in the interest of openness, I have provided him with the video stabilization data anyway, with the above reservations. The position of the footage is the only changing value; anchor point, scale and rotation are fixed. The data reinforce my point about the evenness of the original mechanically stabilized Fox footage: in every single frame of my tracking sequence, the footage was moved only between .6 and 1.0 pixel from the previous frame. That is precisely the picture of a smooth and slow stabilized pan to the left. Yet another issue where Baker was totally wrong.
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