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The limousine at the time of the headshot in Zf313 has been variously described as 'stopped' and 'almost stopped' and 'moving at such and such a speed'. I'm trying to to see if it is possible to definitely work out what in fact happened. When I look at comparative blurs on the limousine and something apparently stationary on the ground, such as feet apparently in the process of being planted on the ground during a step, or an area on the ground that appears in multiple frames, it seems to me that the limousine never stops, it is after all a very heavy (3 metric tons?) vehicle and the forces needed to bring it to a stop/start from where it is moving 2 frames prior to the headshot to Zf314 where it again is clearly moving surely is more than what the motor can supply? So if it is moving, and it seems to slow and obviously accelerates. What is the speed at its slowest? (refer to zl3181s topic, minus the brouhaha of course) I have almost completed a panorama of this period of the zfilm, as soon as its completed I'll post it, while looking at it so far, I can't see any frames missing. comments please??

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The limousine at the time of the headshot in Zf313 has been variously described as 'stopped' and 'almost stopped' and 'moving at such and such a speed'. I'm trying to to see if it is possible to definitely work out what in fact happened. When I look at comparative blurs on the limousine and something apparently stationary on the ground, such as feet apparently in the process of being planted on the ground during a step, or an area on the ground that appears in multiple frames, it seems to me that the limousine never stops, it is after all a very heavy (3 metric tons?) vehicle and the forces needed to bring it to a stop/start from where it is moving 2 frames prior to the headshot to Zf314 where it again is clearly moving surely is more than what the motor can supply? So if it is moving, and it seems to  slow and obviously accelerates. What is the speed at its slowest? (refer to zl3181s topic, minus the brouhaha of course) I have almost completed a panorama of this period of the zfilm, as soon as its completed I'll post it, while looking at it so far, I can't see any frames missing. comments please??

The limo came to a near stop according to the photographical record - a crawl if for no better word. White House Press reporter Merriman Smith said that while the car he was in had stopped for a few seconds ... he could see the President's car and that it had only faltered (slowed) before speeding away. Moorman's #5 photo shows the rear hubcap still turning for the star emblem in the center of the wheel is blurred. Those witnesses that were more behind the car probably did get the impression that the car had stopped. I know of no witness who saw the limo in profile ever make such a claim as seeing the limo completely stop.

Edited by Bill Miller
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The limo came to a near stop according to the photographical record - a crawl if for no better word. White House Press reporter Merriman Smith said that while the car he was in had stopped for a few seconds ... he could see the President's car and that it had only faltered (slowed) before speeding away. Moorman's #5 photo shows the rear hubcap still turning for the star emblem in the center of the wheel is blurred. Those witnesses that were more behind the car probably did get the impression that the car had stopped. I know of no witness who saw the limo in profile ever make such a claim as seeing the limo completely stop.

Bill, can the degree of turn be determined and therefore the distance of arc of tyre surface and therefore the distance of the travel during the time the shutter is opened (minus (perhaps?) the time it takes for the image to register on film emulsion? (ASA?)) Hence the speed of the limousine?

John

great image BTW

Edited by John Dolva
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The limo came to a near stop according to the photographical record - a crawl if for no better word. White House Press reporter Merriman Smith said that while the car he was in had stopped for a few seconds ... he could see the President's car and that it had only faltered (slowed) before speeding away. Moorman's #5 photo shows the rear hubcap still turning for the star emblem in the center of the wheel is blurred. Those witnesses that were more behind the car probably did get the impression that the car had stopped. I know of no witness who saw the limo in profile ever make such a claim as seeing the limo completely stop.

Bill, can the degree of turn be determined and therefore the distance of arc of tyre surface and therefore the distance of the travel during the time the shutter is opened (minus (perhaps?) the time it takes for the image to register on film emulsion? (ASA?)) Hence the speed of the limousine?

John

great image BTW

The implications of all this could be quite far-reaching. If in measuring tyre revolution, comparing elongations as suggested in zf318ls and other ideas around and a definite speed is determined then this can be used to determine timing of events, film authenticities, missing frames, plus crossreferencing to other films to determine their factors, coordinating them to an agreed standard? complicated perhaps but worthwhile I think.

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Bill, can the degree of turn be determined and therefore the distance of arc of tyre surface and therefore the distance of the travel during the time the shutter is opened (minus (perhaps?) the time it takes for the image to register on film emulsion? (ASA?)) Hence the speed of the limousine?

John

great image BTW

I think the best way to do this is to use the Nix film. There may have already been an FBI study on the distance the limo traveled per frame. Write Gary Mack at the 6th floor and see if there is any data on this. The email address is GMACK@JFK.ORG

I have looked at the frame advancement of the limo and have found nothing wrong with it. There were however a couple of instances in the MPI film where the frames were turned around if I am not mistaken. This is easily noticeable and can be corrected without any difficulty. For instance ... the white dot between Jackie and JFK's head between Z315 and Z317 advances equally for the most part. To remove one frame in a line of frames would stick out like a sore thumb for the advancement would take an odd jump forward.

Edited by Bill Miller
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Bill, can the degree of turn be determined and therefore the distance of arc of tyre surface and therefore the distance of the travel during the time the shutter is opened (minus (perhaps?) the time it takes for the image to register on film emulsion? (ASA?)) Hence the speed of the limousine?

John

great image BTW

I think the best way to do this is to use the Nix film. There may have already been an FBI study on the distance the limo traveled per frame. Write Gary Mack at the 6th floor and see if there is any data on this. The email address is GMACK@JFK.ORG

I am referring to the blur of the star in the hubcap : can the degree of turn be determined and therefore the distance of arc of tyre surface and therefore the distance of the travel during the time the shutter is opened (minus (perhaps?) the time it takes for the image to register on film emulsion? (ASA?)) Hence the speed of the limousine?

A good copy of the NIX film would be good to have.

As far as studies by FBI etc I think the info of their conclusions are available, what I'm trying to do is develop methods to verify/dispute that or any other estimates made by other methods.

The implications of all this could be quite far-reaching. If in measuring tyre revolution, comparing elongations as suggested in zf318ls and other ideas around and a definite speed is determined then this can be used to determine timing of events, film authenticities, missing frames, plus crossreferencing to other films to determine their factors, coordinating them to an agreed standard? complicated perhaps but worthwhile I think.

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I am referring to the blur of the star in the hubcap : can the degree of turn be determined and therefore the distance of arc of tyre surface and therefore the distance of the travel during the time the shutter is opened (minus (perhaps?) the time it takes for the image to register on film emulsion? (ASA?)) Hence the speed of the limousine?

My first thought was this could not be accomplished by way of a still photo, but the question you raise is certainly worth inquiring about. I'd still email Gary Mack and possibly Robert Groden for their input. I admire your idea about seeking various approches to double check the facts.

I may be missing YOUR point here but leave it with me, often a bit of thinking sometimes clears things for me. It is precicely the blur or perhaps correctly the elongation of objects during the time that images register of the fil surface that I am interested in.

I applaud what you are attempting to do.

Can you indicate where one might get a good copy of the nix film. Great images BTW.

I think I took mine from Groden's assassination film DVD. It may have been titled "A case for conspiracy."

Below is an example of what I was trying to say at one point. Brennan is sitting on the concrete wall and doesn't move between these frames, but the bluring that takes place gives a false impression that Brennan did move. My concern is how such a blur could effect the accuracy of trying to determine the distance the limo had traveled between frames when such a thing happens.

Edited by Bill Miller
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I am referring to the blur of the star in the hubcap : can the degree of turn be determined and therefore the distance of arc of tyre surface and therefore the distance of the travel during the time the shutter is opened (minus (perhaps?) the time it takes for the image to register on film emulsion? (ASA?)) Hence the speed of the limousine?

My first thought was this could not be accomplished by way of a still photo, but the question you raise is certainly worth inquiring about. I'd still email Gary Mack and possibly Robert Groden for their input. I admire your idea about seeking various approches to double check the facts.

I may be missing YOUR point here but leave it with me, often a bit of thinking sometimes clears things for me. It is precicely the blur or perhaps correctly the elongation of objects during the time that images register of the fil surface that I am interested in.

I applaud what you are attempting to do.

Can you indicate where one might get a good copy of the nix film. Great images BTW.

I think I took mine from Groden's assassination film DVD. It may have been titled "A case for conspiracy."

Below is an example of what I was trying to say at one point. Brennan is sitting on the concrete wall and doesn't move between these frames, but the bluring that takes place gives a false impression that Brennan did move. My concern is how such a blur could effect the accuracy of trying to determine the distance the limo had traveled between frames when such a thing happens.

Bill, the way I see it is that this blur can be used to determine the component of the blur of a moving object that needs to be subtracted from the moving object thus determining speed. The blurry, previously discarded photos of the assassination may yet yield more information. has anyone got a stash of such somewhere?

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I said "I am referring to the blur of the star in the hubcap : can the degree of turn be determined and therefore the distance of arc of tyre surface and therefore the distance of the travel during the time the shutter is opened (minus (perhaps?) the time it takes for the image to register on film emulsion? (ASA?)) Hence the speed of the limousine"

further on this, A joint attempt is being made to develop a methodology to determine the speed of the limousine. A thoought has led to the possible need for the exact dimensions of the tires on that day. Inflation PSI? Tread wear? Brand? comments/info appreciated/welcome

John

Edited by John Dolva
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the longer 'blur' in 313 is approximately 3 1/2 times the width of the area producing it. this area is stationary, therefore this shows the movement of the camera during the 1/35 second that the shutter is open.

the shorter 'blur' is approximately 4 1/2 times the width of the area producing it. therefore the limousine is moving at this point.

the limousine IS moving?!

if the camera was NOT moving in relation to the area on the grass then that would show as an area 5 pixels wide. meanwhile the 2 1/2 pixels wide area on the bar would have travelled W pixels.

the bar is 20 pixels wide at this point.

the bar is Z inches wide.

Therefore the limousine has at this frame travelled Y inches in 1/35 seconds.

the limousine is moving at X mph when Kennedy was shot in the head.

make sense?? help fill in w,x,y and z. pls.

addendum : As far as studies by FBI etc I think the info of their conclusions are available, what I'm trying to do is develop methods to verify/dispute that or any other estimates made by other methods.

The implications of all this could be quite far-reaching. If in measuring tyre revolution, comparing elongations as suggested in zf318ls and other ideas around and a definite speed is determined then this can be used to determine timing of events, film authenticities, missing frames, (plus frame rate!) plus crossreferencing to other films to determine their factors, coordinating them to an agreed standard? complicated perhaps but worthwhile I think.

The bar is approximately, hangonaminute, why do I want the bar width?? hmm... er.

Ok, i know , it would help to determine the actual size of a pixel. the bar is approximately 6 1/2 inches wide (more precise would be good). the bar is 20 pixels wide. one pixel is 0.33 inches.

The dimensions of the area of white on the grass appears to be 5 (x) by 3.5 (y) pixels while the one on the bar appears to be 2 by 2.5. This is from a comparison from image below where in one the elongation appears to be largely in the vertical and the other in the horixontal. Of course this is at this zoom level. The horizontal 'blur' on the grass is here approximately 23 pixels, on the bar it is about 12 pixels.

the over all movement of a pixel on the ground is about 18 pixels, on the bar it is about 10 pixels.

so if the ground is stationary the bar has moved 8 pixels or about 2.5 inches in 1/35 seconds. this is a speed of 91 inches in one seconds which is the equivalent of 9100 yards in one hour which is 5.2 miles per hour??

could someone check this figuring/reasoning for me please?

Edited by John Dolva
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other elongated object pairs

(this is an earlier (see zf318ls) post of mine, I've since figured out that dimensions from a horizontal and a vertical pair may give a better indication of object/area size)

addendum: I still can't get it out of my head that somehow an approach that looks at comparing the difference in angle of the 'blurs' can be useful. comments??

Edited by John Dolva
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on a previous post in zf318ls

here the direction of travel length of the ground area is 56.5 pixels and the bar area 27 pixels the area on the grass at this zoom is approx 10 pixels and the bar approx 4 pixels. so again, if the area on the grass is stationary the bar has moved 46-23 pixels ie 23 pixels, at this zoom taking the bar at 38 (from checking with the less blurred zf317) pixels, so if i zoom it back to the previous calculation where the bar is about half this the bar has travelled about 12 pixels. or 3.75 inches in 1/35 seconds. this is 132 inches in one second or 13125 yards in one hour or 7.5 mph.

Hmm so far so good. however a more careful (if the reasoning is correct) measuring is necessary. also an exact dimension of the bar would be good (anyone?).

further hmmm edit: this seems a phenomenal acceleration??or does it? anyway its the method thats the thing at this stage, more accurate figures would be the ones to look at for results. perhaps some table like this could be generated.

further edit: another measurement could yield an aceleration rate if one assumes greer floored it? did he? does the motor respond in such a way? other issues not still answered, how fast does the image register on the film surface? correlation with other films calculations needed.

further: at all stages error margins need to be included, for example the above calculations may be 6.2 and 6.5 mph respectively, i dont know at this stage, howeveras yet seems ok to me, of course i may be missing something very obvious, hence input much appreciated (let alone appreciated byanyone interested in issues of speed, authenticity etc. as Ive already stated, analysis of soingle frame photos may contain lots of info previously not derived. however, i've gotn a day with kids now so will check back again tonight.

Edited by John Dolva
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verification / debunking needed:

1 mile = 1760 yards

(35d/36 x 60 x 60 )/1760 where i is inches per pixel,stationary area length of movement s , moving area length of movement m. i(s-m) is inches of movement d.

so

1.9886363636363636363636363636364i(s-m) = v mph at zframe #

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a b a-b a+b c = a-go d = b-bo c-d c+d d-c v

313 24 12 12 36 17 10 7* 27 -7 6.2

314 18 6 12 24 11 4 7* 15 -7 6.2

315 10.5 7 2.5 17.5 3.5 5 -1.5 8.5* 1.5 7.5

316 17 5 12 23 10 3 7* 13 -7 6.2

317 13.5 5 8.5 18.5 6.5 3 3.5 9.5* -3.5 8.5

318 25 12 13 37 18 10 8* 28 -8 7.1

319 10 14 - 4 24 3 12 -9 15 7 8

320 22 7 29 15 5 10* 20 -10 8.9

321 12 5 7 17 5 3 2 8* -2 7.1

322 12 6 6 18 5 4 1 9* -3 8

27 pixels travel between frames 311 and 312 at 6.2 mph = 12 inches between frames = 9.1 frames per second, therefore 1 frame is missing between each pair of frames???? arrgghh thats not the result I expected.. what's going on here.

theres lots here I can't grasp (I'm not a mathematician, if someone is pls help, I don't want to waste my time on a faulty premise here. though I am learning stuff which is not so bad I suppose)

issues that need addressing,

width of bar, error analysis, understanding the direction of the elongation , on some frames its one way on others the other, the actual movement is dependent on how the camera has moved overall, while the difference in movement should yield result, that difference is sometimes an addition sometimes a subtraction. hmm...wish I had someone to nut over this with. oh well I'll just muddlle on.

Edited by John Dolva
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[...]

27 pixels travel between frames 311 and 312 at 6.2 mph = 12 inches between frames = 9.1 frames per second, therefore 1 frame is missing between each pair of frames???? arrgghh thats not the result I expected.. what's going on here.

[...]

perhaps the Zapruder camera ran at 48fps instead of 16fps [FBI 18.3fps] as attested too -- in the optical film printing these frames were ommitted [every other frame-dropped]?

If untreated MPI images were used in your study, you're using MPEG2 images running at 30fps [2 fields per frame - odd scan lines: upper field - even scan lines: lower lower. note: this field order may be reversed, I can't remember]. When viewing individual frame, as a result; may cause slight verticle shift in blur, or horizontal blur broadening and measurable image softening.

If you have the MPI DVD, step through the frames as numbered, you'll see the same frames held for 2-3 frame counts... the standard for MPEG2 images (DVD form) is 29.97fps, if drop frame (somewhere in they're (MPI) process that COULD of been introduced, 30fps is straight NTSC video -- the Zapruder Film is/was rated at 18.3 frames -- best guess by the Fed -- we have no idea how many frames passed through the gate of Zapruders camera that day, or prior - we have no idea the exact feet/inches length of the Zapruder film - when loaded into OR unloaded from the Zapruder B&H414 camera.

Why seeing the film in its unslit form was so important, which of course nobody has any idea if unsplit side-by-side images exist -- especially with edge printing employed during the "optical print" stage.

Edited by David G. Healy
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