Merged Discussion of femr's video data analysis

[ozeco41]

Agreed.


Since you suggested it so nicely, I'll call you on your second point.


That highlighted statement is incorrect. femr2 is holding NIST to a higher standard than he has set for himself....

I understand your point and will reserve judgement at this stage. This discussion risks going further into detailed analysis of another member than I would want to go whilst that member is an uninvolved third party.

...He basically admitted as much in this exchange:
...Note that femr2's primary criticism of the passage he quoted is that NIST failed to use the word "approximately" for a third time in front of "gravitational acceleration". That omission is the basis for femr2's repeated assertions that NIST was "wrong" to claim acceleration at 1g. Note also that femr2 is the person who has been inserting the word "exactly" in front of "gravitational acceleration"...

Your argument noted - I will reserve judgement.

...You're free to argue that femr2 deserves a pass because he prefers to post at a JREF Forum instead of publishing a document of professional quality...

I think 'deserves a pass' is the wrong criterion and also wrong as a generalisation. I am of the opinion that:

• femr2's technical claims are worthy in their own right of consideration on merit. Members are free to address those technical comments. In that setting my overall suggestion is 'read them in context'. I am strongly cautioning against accidental reading femr2's claims out of context and I am critical of the practice of deliberately taking them out of context. On top of that I am critical of the practice of making deliberate false accusations by bringing in matters not subject of the scope of current discussion. There are legitimate ways of argument which could work around that last proviso but I have not seen them used so won't expand further on that aspect: AND
• femr2's choice of strong denigratory language is not the choice I would make if I was coming to a polarised forum such as this knowing that I had been classified as a member of the 'out group' and I was seeking to make valid technical claims. Then again I doubt I would be going as an outsider to a 'truther' site and it is a poor analogy - the warfare is strongly asymmetric in terms of willingness to accept representatives of the 'other side'

Those two aspects can be totally opposed in value judgement so they don't add together to make either a 'pass' or a fail. Depending on the technical merit of any specific claim that technical part could be anything from fail through to honours pass

...Nevertheless, when femr2's writing is judged by the same standard he has set for NIST, femr2's posts have been

Those are femr2's words, not mine. In my opinion, after taking femr2's choice of publishing venue into account, femr2's writing has often been hypocritical, boring, and/or sloppy, but has not always been nonsensical. His recent argument became nonsensical only when he augmented his misinterpretation of NIST's statement with his indignant denial of interest in trailing digits.

Your further comments noted - same comment as before - I reserve judgement for now.

 

[alienentity]

Alrighty, I spent some time this afternoon very carefully checking the FOIA released video of the WTC 7 collapse, so that I could accurately locate the start of global collapse.

This is because Femr2, using different methods, and different locations, has challenged the NIST observation of 5.4 sec for the 18 stories to fall. Many truthers also do exactly the same thing.

Now, Femr2 seems to have a notion that his methods are superior to any other which has been applied, but I disagree with that idea: I think that by observing the macro deformations of the building as it begins to collapse, we can safely identify the start of the global collapse - how else would you fairly describe the motions of the building except that it is collapsing?

One can argue that the deformations are somewhat non-vertical (although nobody has yet quantified them) and so this means the building was not collapsing - I think that idea is false, and I also think that the main reason why both truthers and other detractors of NIST insist on such is because by allowing it, you must allow NIST's overall timing, and you must allow that the initial phase of global collapse was certainly not 'instantaneous' or at 'freefall speed'.

So basically if you accept the idea that a building behaving in this way is not collapsing, you are doing so just to spite NIST, but not for scientifically sound reasons.

Borrowing methods from Femr2 I created a pulsating loop, magnified, which unmistakably demonstrates the deformation of the building during a 1 second fragment (actually 1 second and 6 frames )
By the end of that short loop, the building is quite deformed, so is in collapse. Splitting hairs one could argue that I might be 10 frames too soon - maybe I am, but that doesn't change the overall time by very much. I could also be underestimating by 10 frames!
All these measurements are somewhat subjective and depend on what you choose to measure - and that is not something which is set in stone, but will vary on the method and the person doing the measuring.

Just to ice the cake, I deliberately stopped timing just before the building top disappears, thus artificially shortening the elapsed time.....
So really what we have is a legitimate range of possible times, anywhere from 5.3 to 5.6 seconds.

The NIST time is reasonable and more or less accurate, IMO, and there's no reason to keep trashing it as if it were the work of Satan.

Cheers

AE

 

[pgimeno]

(BUT not pgimeno's additional claim that NIST went too far which is applying pgimeno's standard not NIST's)

To clarify, that's a personal opinion, not a claim. As such, it is of course based on my own standards. Seems I wasn't clear enough about that when I said e.g. "in my opinion" or "I don't think was necessary".

Let me also clarify another point. If femr2 limited his discussion to the movement of the northwest corner and how he thinks it should be interpreted, whether to correct cmatrix or for the sake of it, I would have let it be. What made me jump in was, in one side, his repeated unfair smearing of NIST (see e.g. post #893 which partly motivated my post #914 where I rejoined the discussion), which as I have said aligns with MT's smearing campaign against NIST and Bažant, and in the other side his claims that his data reveals features about the collapse and pre-collapse sequence that disprove NIST (see post #926). Had he not made such claims nor have used his results to unfairly attack NIST, I would probably not have intervened, as I have no reason to object to his methods or data. My focus has been on these two points, that were not brought up by me in the first place. My claims of irrelevance have always been related to his claims of revealed pre-collapse features based on his data, as I don't think he can validly claim that kind of conclusions to be true without publishing them and letting them pass a competent review (not only peer review, but post-publication review; Benveniste's "water memory" article in Nature comes to mind as an example of why being published is not enough).

 

[ozeco41]

To clarify, that's a personal opinion, not a claim. As such, it is of course based on my own standards. Seems I wasn't clear enough about that when I said e.g. "in my opinion" or "I don't think was necessary"...

Yes - you were explicit - I was using it to differentiate two examples - possibly the word 'claim' wasn't the best one to use. There was no doubt as to your meaning and that was why I used it as the example of someone doing it right and covering the bases.

...Let me also clarify another point. If femr2 limited his discussion to the movement of the northwest corner and how he thinks it should be interpreted, whether to correct cmatrix or for the sake of it, I would have let it be. What made me jump in was, in one side, his repeated unfair smearing of NIST (see e.g. post #893 which partly motivated my post #914 where I rejoined the discussion), which as I have said aligns with MT's smearing campaign against NIST and Bažant, and in the other side his claims that his data reveals features about the collapse and pre-collapse sequence that disprove NIST (see post #926)....

I have several times expressed my concerns about the excessive use of black and white language when the issues are shades of grey.

My claims of irrelevance have always been related to his claims of revealed pre-collapse features based on his data, as I don't think he can validly claim that kind of conclusions to be true without publishing them and letting them pass a competent review (not only peer review, but post-publication review; Benveniste's "water memory" article in Nature comes to mind as an example of why being published is not enough).

I have also posted my views on the appropriateness of the professional peer review journal process in the context of an Internet debate. The truth or otherwise of claimed fact rests in the truth or otherwise of said fact. Whether someone wishes to take the journal path to support an Internet debate is their choice - generally I would expect journal publishing to be driven by some other higher purpose and the Internet debate essentially getting a side benefit. I suggest that most issues of fact needed for a reasoned Internet debate can be settled by reasoned argument. The main reason we see 'peer review' come up so often is because truthers will not use reasoned argument - so 'peer reviewed' journal article looks like the tempting bit of extra authority to hit the truther with. A waste of time because the goalposts will move and/or the truther takes the opportunity to derail into discussion of the procedure etc etc ....you will get the idea.

 

[ozeco41]

Alrighty, I spent some time this afternoon very carefully checking the FOIA released video of the WTC 7 collapse, so that I could accurately locate the start of global collapse.
...The NIST time is reasonable and more or less accurate, IMO, and there's no reason to keep trashing it as if it were the work of Satan.

Cheers

AE

Well done AE - some competition in the marketplace.

 

[W.D.Clinger]

I have several times expressed my concerns about the excessive use of black and white language when the issues are shades of grey.

I have also posted my views on the appropriateness of the professional peer review journal process in the context of an Internet debate. The truth or otherwise of claimed fact rests in the truth or otherwise of said fact. Whether someone wishes to take the journal path to support an Internet debate is their choice - generally I would expect journal publishing to be driven by some other higher purpose and the Internet debate essentially getting a side benefit. I suggest that most issues of fact needed for a reasoned Internet debate can be settled by reasoned argument. The main reason we see 'peer review' come up so often is because truthers will not use reasoned argument - so 'peer reviewed' journal article looks like the tempting bit of extra authority to hit the truther with. A waste of time because the goalposts will move and/or the truther takes the opportunity to derail into discussion of the procedure etc etc ....you will get the idea.

I understand that many here use "peer review" as a kind of taunt, and I share your annoyance with that.

You, however, appear to have bought into one of the taunters' misconceptions, which is that peer review's only purposes are to act as a filter keeping nonsense out of the peer reviewed literature and to provide a stamp of authority on articles that pass muster. Peer review does have some of those effects, but those effects are not its only purposes.

Another important purpose of peer review is to help authors to improve their articles before publication. That effect of peer review would be especially helpful to amateur researchers, which is a group that includes many engineers and other professionals who have never published a research paper.

Regardless of any professional qualifications, femr2 belongs to that group of inexperienced researchers. He has seldom described his data and techniques with the detail necessary for others to duplicate his results or even to evaluate them properly.

Consider, for example, the variety of graphs he has posted in this thread. Early on, I downloaded his data and tried to duplicate his results, but was often stymied by his poor documentation. In many cases, such as the first graph of post #864 in this thread, he provides nothing more than vague description of how his graphs were computed, or even what they're supposed to mean. That's especially obvious in post #864 because his animated GIF contains 24 frames, each showing what appears to be a different red line.

Presumably those red lines are supposed to illustrate the variety of different results you can get when you "use whatever methods you please to transform position/time into acceleration/time with whatever noise-treatment you please." In later discussions, femr2 selected just one of those 24 red lines, treated it as the only correct line, and used the differences between that red line and NIST's graphs as the authority for his assertion that NIST's graphs were "wrong".

So far as I recall, femr2 has never told us the specific methods he used to produce that particular red line, nor has he told us why he chose that particular red line as his authority instead of using one of the 23 other red lines he had computed. He has also refused to display any kind of confidence interval for his favored red line, and has heaped derision on several good suggestions that he provide some estimate for its interval of uncertainty, even though the existence and nature of his 23 other red lines would seem to imply considerable uncertainty in the red line he wants us to accept as authoritative.

That's amateurish. I don't mean to suggest that femr2 is being nefarious, although I could not blame anyone for drawing that conclusion. I think femr2 just cares more about producing videos and pulsating GIFs for the YouTube generation than about producing research of professional quality.

I think his research would benefit greatly from peer review, but I understand and accept that he will never submit his work to peer review. That's his choice, and our loss as well as his.

 

[ozeco41]

...Another important purpose of peer review is to help authors to improve their articles before publication. That effect of peer review would be especially helpful to amateur researchers, which is a group that includes many engineers and other professionals who have never published a research paper....

Yes - I comprehend the range of benefits

...I think his research would benefit greatly from peer review, but I understand and accept that he will never submit his work to peer review. That's his choice, and our loss as well as his.

Understood.

 

[femr2]

Alrighty, I spent some time this afternoon very carefully checking the FOIA released video of the WTC 7 collapse, so that I could accurately locate the start of global collapse.

You are still using the cam#3 viewpoint. I have repeatedly highlighted that the perspective of that viewpoint is the source of the issue, and that cross-check with the Dan Rather viewpoint is the easiest route to resolve it.

I have highlighted that the initial motion in that region of the cam#3 viewpoint is primarily north-south rather than vertical.

I have provided you with a trace for the Dan Rather viewpoint which covers the NIST 5.4s period...
http://femr2.ucoz.com/_ph/7/842535832.gif

Where would you place T0 ?

The *kink* is the problem, as it is thought by many to be a vertical kink in the roofline. It's primarily north-south.

Here's a frame from the Dan Rather viewpoint after the building is well on it's way down...
http://femr2.ucoz.com/_ph/7/321729423.png

Where is the kink ?

This is because Femr2, using different methods, and different locations, has challenged the NIST observation of 5.4 sec for the 18 stories to fall.

And a different viewpoint so I don't replicate NISTs mistakes.

Now, Femr2 seems to have a notion that his methods are superior to any other which has been applied, but I disagree with that idea

Please upload your trace data.

I think that by observing the macro deformations of the building as it begins to collapse, we can safely identify the start of the global collapse

Eyeballs are not good for the purpose imo. Sub-pixel accurate tracing techniques reveal very fine motion detail.

how else would you fairly describe the motions of the building except that it is collapsing?

Twisting.

One can argue that the deformations are somewhat non-vertical

One is, and one has posted a frame from the Dan Rather viewpoint with a really easy way to see that the *kink* is, well, basically not there.

(although nobody has yet quantified them)

As I said, I'll dig you out some links from the911forum. We've some pretty good estimations.

and so this means the building was not collapsing - I think that idea is false

Who said that ? Not me. The issue I have is with the T0 definition, especially as the NIST graph is specifically labelled vertical, when the initial motion is not vertical in that region.

and I also think that the main reason why both truthers and other detractors of NIST insist on such is because by allowing it, you must allow NIST's overall timing, and you must allow that the initial phase of global collapse was certainly not 'instantaneous' or at 'freefall speed'.

Soapboxing unnecessary here. Don't do it.

So basically if you accept the idea that a building behaving in this way is not collapsing, you are doing so just to spite NIST, but not for scientifically sound reasons.

Nonsense.

Borrowing methods from Femr2 I created a pulsating loop, magnified, which unmistakably demonstrates the deformation of the building during a 1 second fragment (actually 1 second and 6 frames )

Is it vertical motion ?

By the end of that short loop, the building is quite deformed, so is in collapse.

You have created your own goalposts.

Splitting hairs one could argue that I might be 10 frames too soon - maybe I am, but that doesn't change the overall time by very much.

That's about a third of a second. Not to be idly thrown around in this context.

The NIST time is reasonable and more or less accurate, IMO, and there's no reason to keep trashing it as if it were the work of Satan.

See all my repeated points above.

 

[femr2]

You don't have a valid justification to claim this is a mistake.

Mistake ? It's simply false. Behaviour of one horizontal position in video != behaviour of entire facde. Full stop.

As a remainder, your graph shows that the acceleration was within 32.5±7.5 ft/s² for about 2.25 seconds, therefore in the lack of any error analysis you can't validly claim NIST is wrong.

Blind NIST support. Howabout 0.0+/-200 ft/s^2 for 10 years ?

 

[pgimeno]

So far as I recall, femr2 has never told us the specific methods he used to produce that particular red line, nor has he told us why he chose that particular red line as his authority instead of using one of the 23 other red lines he had computed.

FWIW, I think the explanation for that is in post 564. It seems to imply that it's a polynomial fit for even degrees from 0 to 50, and I would say he chose degree 50 just because "higher is better".

But as always, he actually never explained, so don't trust my guesses.

 

[femr2]

That was before femr2 explicitly denied Oystein's suggestion that femr2 has been talking about the trailing digits

I was referring to this comment...

Did cmatrix have a valid argument for the relevance of precisely 2.25s, rather than 2.24 or 2.26s?

Context.

 

[femr2]

Note that femr2's primary criticism of the passage he quoted is that NIST failed to use the word "approximately" for a third time in front of "gravitational acceleration". That omission is the basis for femr2's repeated assertions that NIST was "wrong" to claim acceleration at 1g. Note also that femr2 is the person who has been inserting the word "exactly" in front of "gravitational acceleration".

Do I really need to remind you why the details and specific wording are a problem ?

Hint: cmatrix.

 

[femr2]

In later discussions, femr2 selected just one of those 24 red lines, treated it as the only correct line, and used the differences between that red line and NIST's graphs as the authority for his assertion that NIST's graphs were "wrong".

Incorrect. I have constantly (I think) made sure that the velocity profile graphs are described as *more accurate*, *representative of*, etc.

So far as I recall, femr2 has never told us the specific methods he used to produce that particular red line

It's in the thread somewhere I'm sure.

 

[pgimeno]

h) They applied their interpretation to the entire north face.

You don't have a valid justification to claim this is a mistake.

Mistake ? It's simply false. Behaviour of one horizontal position in video != behaviour of entire facde. Full stop.

Yet you lack the information of why they made such extrapolation, therefore you lack the basis to claim such falsehood.

Blind NIST support. Howabout 0.0+/-200 ft/s^2 for 10 years ?

Not blind NIST support. Merely highlighting why without an error analysis, your claim of sloppiness in the wording doesn't hold water. If you restrict to talking about your data without spreading that unjustified claim at the same time, I will have nothing to criticize. If you really prove your assertions, something you have attempted but not managed, I will accept it. In the case of the gravity wording you're doomed to fail, because as has already been noted (especially by W.D.Clinger) the qualifications in the wording were accurate enough, and sufficient to indicate that they were talking about an approximate gravity acceleration, something also highlighted by their own graphs.

 

[femr2]

Yet you lack the information of why they made such extrapolation, therefore you lack the basis to claim such falsehood.

Dear me. The North face != a wandering horizontal position near the middle of the face.

Merely highlighting why without an error analysis, your claim of sloppiness in the wording doesn't hold water.

I've posted this list of some of the issues I have...

NISTs choice of location and methodology for their WTC7 position/time trace is a significant problem for their data because...
a) They misinterpreted initial motion as vertical rather than north-south (as they did not take account of the initial twisting motion visible from the Cam#3 viewpoint).
b) They did not perform perspective correction.
c) They did not perform static point extraction (the removal of camera movement from trace data. Even though the view may look static, it is not.)
d) They did not track a feature at all, but a horizontal position. As the building did not descend completely vertically, but included some east-west movement, their data is actually of a wandering horizontal point, not a feature on the facade.
e) In order to obtain a trace from their initial point to their stated final point they had to *splice* together two traces from completely different horizontal positions, which without taking account of the perspective and distance shearing effects makes the data further skewed.
f) They did not treat the base video data correctly, using an interlaced copy of the video (the actual copy they used is available within the recent FOIA releases. I have the original)
g) They did not perform a per-frame trace, but instead skipped frames, reducing the sampling rate considerably and reducing available data redundancy for the purposes of noise reduction and derivation of velocity and acceleration profile data.
h) They applied their interpretation to the entire north face.
i) It is highly probable they used a manual process to record the trace data, rather than the sub-pixel accurate automated feature tracing methods I employ.

These are some of the reasons their data is shoddy and their method sloppy.

If you restrict to talking about your data without spreading that unjustified claim at the same time, I will have nothing to criticize.

Which of the list above do you have issue with ?

Sounds more like talk about your own data, but don't you dare criticise NIST or their data

In the case of the gravity wording you're doomed to fail, because as has already been noted (especially by W.D.Clinger) the qualifications in the wording were accurate enough, and sufficient to indicate that they were talking about an approximate gravity acceleration, something also highlighted by their own graphs.

Ye gads. How do you expect folk with a rigid stance on the exact words to change their viewpoint if you are not willing to simply say yes, NIST should have said *approximately* ? You'd criticise me if I did the same.

 

[Sherman Bay]

Andy points a powerful telescope at the TV screen from 10 feet away, cranks it up to maximum power, and then snaps a picture. The result is a photo of a single pixel. "That proves me right!" Andy exclaims. "This pixel is the same color as the the lunar surface. Therefore the show must be about the Moon. Prove me wrong!!"

I like your insightful analogy.

But the "Andys" don't stop there. After being confronted with the obvious refutation to each and all their claims, they make a video loudly and angrily criticising the Bettys of treason and plotting to overthrow the government, poisoning the human race, and destroying civilization, not to mention having hot sex with squids.

 

[Stellafane]

...No, Stellaphane was suggesting that presenting information which would tend to support the notion of "core failure beneath the East penthouse of WTC7 propogating upwards and followed by descent of such through the building" was a tiny bit of nothingness. Given that such behaviour is the fundamental root of the NIST most probable cause of failure, the statement by Stellaphane is ludicrous.

Well, just to be clear, what I considered a tiny bit of nothingness (or per my original post, a single pixel) was more your focus on this point, a point about which I have zero interest until you get me past all the other layers of massive somethingness that say your concern is misplaced, irrelevant, and almost certainly wrong. Or to put it another way: It's possible you may be onto something -- I don't think you are, but anything's possible, I suppose -- but I'm not going to give it a second's worth of thought unless you can explain to me all the other mountains of evidence that says 9/11 happened precisely the vast majority of people think it did. Single pixel that might be the Moon surrounded by a TV screenful of frogs, and all that.

BUT...all that was posted when this was part of a more open, free-for-all thread. Now that this thread has been created specifically to discuss your specific pixel, my posts designed to call attention to all the other 9/11 pixels are by definition a derail, so I will now bow out.

 

[pgimeno]

Dear me. The North face != a wandering horizontal position near the middle of the face.

Indeed, and yet they did that extrapolation. Why did they?

Can you answer that simple question (with sound arguments)?

I've posted this list of some of the issues I have...

And I'm focusing in two precise points, which were the ones you brought up first, namely the claim about the wording on acceleration (which you having including on the list) and the one about extrapolating the movement to the whole facade (which is point h).

Sounds more like talk about your own data, but don't you dare criticise NIST or their data

No, it's more like: criticize with a solid base, or don't. As a counterexample, I have admitted that NIST's wording on the WTC1 antenna inclination in the first instants was wrong, and have identified the probable cause for such slip.

Given the moot importance of the case in point, your highlighting of the alleged sloppiness on their side, even if it were so, amounts to just unreasonable smearing. I have no issue with you claiming that your data is better, and I may probably agree; my issue is with your focus on criticizing the work of NIST ignoring the context, with the implicit charge that it invalidates part of their conclusions.

I know, where did I say that, please provide citations, blah blah blah. Don't bother, I won't answer, it's clear enough.

Ye gads. How do you expect folk with a rigid stance on the exact words to change their viewpoint if you are not willing to simply say yes, NIST should have said *approximately* ? You'd criticise me if I did the same.

*I* wouldn't. But I still see nothing wrong in with NIST's wording in its context.

 

[alienentity]

I have highlighted that the initial motion in that region of the cam#3 viewpoint is primarily north-south rather than vertical.

Precisely why viewing a large portion of the curtain wall is more useful for determining the deformation - it is fairly easy to see that a large area of the building is moving vertically and horizontally, although not uniformly!

That is why measuring the motion of one pixel doesn't give you a meaningful perspective, and why a different method (the one I'm using) gives you a better perspective of the early motions.

I have provided you with a trace for the Dan Rather viewpoint which covers the NIST 5.4s period...
[qimg]http://femr2.ucoz.com/_ph/7/842535832.gif[/qimg]
Where would you place T0 ?

See above.

Here's a frame from the Dan Rather viewpoint after the building is well on it's way down...
[qimg]http://femr2.ucoz.com/_ph/7/321729423.png[/qimg]
Where is the kink ?

You're trying to introduce an unnecessary distraction into the discussion, when I was clearly looking at pre-kink, T=0 to T= +/- 1 sec motion.
The whole point is to determine a fair value for T=0, which I have done.

And a different viewpoint so I don't replicate NISTs mistakes.

The building deformations are quite evident from this viewpoint, no need to pretend that they can't be seen. There is no mistake.

You are attempting to invalidate the entire clip, ie. to handwave the results. That's not very nice

Eyeballs are not good for the purpose imo. Sub-pixel accurate tracing techniques reveal very fine motion detail.

Eyeballs must be used at some point, no valid reason to reject direct observation.

Twisting.

You're still doing it - pretending that building motions are not collapse. It was clearly both deforming horizontally and vertically. You can't really have one without atother, y'know. Not bloody likely.

Who said that ? Not me. The issue I have is with the T0 definition, especially as the NIST graph is specifically labelled vertical, when the initial motion is not vertical in that region.

That's the trouble with quibbles, (sorry for the Star Trek reference) - they distract from the big picture. The big picture in this case is that the initial deformations are less pronounced than the motions of some other collapsing structures of WTC 7 - namely the large mechanical W Penthouse etc.

This is something missed by virtually all truthers, and yourself as well - something which makes you curiously unobservant (and this ain't the first time you've missed the obvious as I've noted above) - those structures fall into the building as the global collapse begins, so they were moving faster than the curtain wall or North wall.

Not only does this provide strong evidence of a preceding internal collapse, but it also demonstrates that the building was not collapsing as one rigid mass, that the curtain wall was not accelerating at G as the column buckling happened, and that tracking any single point of the collapse is not going to give you the magical number you're looking for.

And the kicker is none of that is going to answer the ultimate question - was the building destroyed by fires or controlled demolition?

Since almost all of us are mainly interested in that question, and not the infinite minutia of the exact building motions as the global collapse began, the general information about the approximate time it took for the building to fall out of sight gives an appropriate frame of reference for the layman.

Soapboxing unnecessary here. Don't do it.

You don't control what I think or write. Sorry. I suggest you look for your submissive buddies elsewhere...

Is it vertical motion ?

Duh

You have created your own goalposts.

So have you. Your point?

That's about a third of a second. Not to be idly thrown around in this context.

Well, 10 frames ain't gonna get you down to 4.4 seconds, which is the figure you claim. At best, you get a range between about 5.2 and 5.8 seconds, with a median of 5.5.
The NIST 5.4 is certainly justifiable and reasonable. It is not 'fraud', it is not 'wrong' - it is a reasonably accurate measurement.

As you may have noticed by now, I am aware that all these attempts to quantify, to measure, base themselves on criteria which are somewhat arbitrary. The worst element is trying to determine whether early motion is collapse or not - I've outlined my reasons for accepting the deformation as the onset of global collapse, you've rejected them.

Most reasonable people probably don't care and won't see the relevance of quibbling about .5 seconds. Neither do I, except that you seem determined to deny that anybody can hold a valid opinion which does not agree with yours.

And that, my friend, is more about the quirks of individual personality rather than being directly relevant to the overarching question as to whether the building fell because of fire or controlled demolition.

I'm going to leave it at that.

 

[dafydd]

* BUZZ*
Wrong again!
The problem here is:
Why are you posting all this in the 911 CONSPIRACY sub-forum?
No one has a legit prob with NIST being fleshed out.
If that is truly your desire. I think you chose the wrong audience! Maybe it's just me?

What is the right audience? I still have no idea what Femr is rabbiting on about.