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John Dolva wrote:

I have been re-reading this series of posts and they are ridiculous, Jack (and I know you said you won't respond) You state "He put together the Z-panorama which you have been using". NO, I have never used any panorama put together by anyone else, I have never said so. If I had been doing so I would have mentioned where it came from. I didn't mention any such thing.

Therefore an unsupported statement that I was using that is the same as an accusation at worst of plagiarism, at best an accusation of dishonesty or deceit. Furthermore, while putting together that panorama series I was unaware of any other such work.

dgh01: entirely possible -- there's room for disagreement in this thread -- appears you stated you USED Costella's frames of the MPI frames as opposed to the panorama of Elm Street -- if so, some will stand corrected. I might add if your using those frames for your analysis - I believe they've been deblurred, pin cushioning and barreling corrected

The follow on statements and actions based on this false premise and my response to it, I feel is beneath contempt.

dgh01: you want to sell ANYTHING to the Research community, then the world at large, you'd get use to it! Even if you SOLVE it! And you won't via photo analysis/interpretation without access to camera originals or 1st generation dupes

edit: The furthest I have thought on this is that some relationship between the DIFFERENCES quite apart from the indeterminable variables might provide some universal constant, even in terms of methodology. All along I have thought that there is something in the difference in the angle of the two blurs may be uniquely shaped by just the speed when comparing the two blurs on a stationary and a moving object. Input welcome.

dgh01: and IF the current imagery you're using is "deblurred", what then?

Your inital assumption, the use of unfettered Z-frames is the best route, where you'll find them is another question

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Dear Gentlemen,

I would like to draw your attention on a very important characteristic of the B&H 414PD camera.

The shutter speed!

This one was very low!

It was only equal to 1/35 of a second!!!

By taking account of this very long duration between the opening and closing of the shutter, it is obvious that the general sharpness between the static bystanders in the background and the Limo in the foreground, and this in several Z-frames, represents an absolute technical impossibility.

The best examples being Zf-303, Zf-305, Zf-307, Zf-309!!!

Edited by Marcel Dehaeseleer
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David, thank you, I must admit that 'in the heat of the moment' I didn't realise the significance of your statement re deblurring. Hmm I've always regarded the elongation of the various objects in the frames as blurring. Perhaps I've been using the wrong term. Michel's post helped me to understand this further.

so: my current thinking on this is that the elongation of the various objects in the frames is caused by the combination of movements of camera and objects during the time of shutter being opened, (taking perhaps into account the time that first registry on the film emulsion occurs?). The camera movement can be determined by considering ground as stationary. From this the speed of movement of moving object can be deduced?

*this seems to be separating as another issue of speculation on my part : I have difficulty thinking beyond a speculation that there is perhaps some 'constant' to be determined from the difference in angle between the elongation of a stationary and a moving object. Any comments that put's my thinking right in this appreciated.

Further: I, in hind sight can see that I overreacted in accusing someone of accusing me of plagiarism. I apologise for my part in diverting attention away from more important issues. David, I am learning that you are right re research atmosphere. However, right or wrong aside I think it has been an instructive episode. I hope that in the future I will deal with such things more elegantly.

Marcel, Is a schematic for the Bell Howell available? On a side issue I need to find out if there is any way an image from the viewfinder can get onto the film surface.

John

Edited by John Dolva
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Marcel, Is a schematic for the Bell Howell available? On a side issue I need to find out if there is any way an image from the viewfinder can get onto the film surface.

John

John,

The B&H camera hasn't a "Reflex" viewfinder!

In other words the viewfinder and the lens are superposed, this induces a slight shift due to the parallax.

Nevertheless the zoom is "coupled" with the viewfinder and the parallax is +/- corrected.

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correction: David, I must have had another thread in mind , please read David wherever I said Shanet in previous post, sorry.

hmm I corrected that plus a use of stephen at wrong place. trying to do too much at one time. Multitasking hyperthread malfunction!

further edit: Marcel, I'm not familiar with those term's, My reading after your post doesn't seem to be clear to me regarding the viewfinder main lens relationship. Do I understand correctly that the image through the viewfinder travels through a separate lens to the one that projects an image onto the film without ANY opening between the two?

Edited by John Dolva
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The dimensions of the area of white on the grass appears to be 3.5 by 5 pixels while the one on the bar appears to be 2 1/2 by 2. 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' in the diagram at the beginning of this topic is here approximately 23 pixels.

(well there goes my attachment quota, I'll see about getting more (anyone knows about how that goes?))

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Comparative Blur Analysis to Derive Speed of Limousine in Frames from the Zapruder Film CBADSLFZF  : CBA for short :up

Levity aside. These are the blurs at zf313. The short one is from the limo. The long is the same one as the long on the other pics. Zoom is different on all but I think its the relative lengths/angles? that may yield some formula.

John,

There certainly are several factors going on that effects the amount of bluring being seen on the Zapruder film. One is the speed at which an object is moving. Another factor is ofcourse the panning blur caused by Zapruder. Like John Costella pointed out - some things within a film frame may be blurred at different levels. An object moving in the direction of Zapruder's pan may not blur as much as let's say ... a stationary object. I would suggest using a film taken further away where such factors do not have to come into play. The Nix film may be a better choice for seeking the speed of the limo at various points.

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John,

There certainly are several factors going on that effects the amount of bluring being seen on the Zapruder film. One is the speed at which an object is moving. Another factor is ofcourse the panning blur caused by Zapruder. Like John Costella pointed out - some things within a film frame may be blurred at different levels. An object moving in the direction of Zapruder's pan may not blur as much as let's say ... a stationary object. I would suggest using a film taken further away where such factors do not have to come into play. The Nix film may be a better choice for seeking the speed of the limo at various points.

Bill,

from my previous posts : during the time that the shutter is open, the camera doesn't necessarily move in a consistent way, what I mean is that the camera may for example be almost stationary for a moment then move and that or any movement might be accelerating/ decelerating/ or whatever, so it is the difference in movement between the moving car and the stationary ground that to my thinking could yield results ???

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.

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

John

Edited by John Dolva
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The dimensions of the area of white on the grass appears to be 3.5 by 5 pixels while the one on the bar appears to be 2 1/2 by 2. 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' in the diagram at the beginning of this topic is here approximately 23 pixels.

(well there goes my attachment quota, I'll see about getting more (anyone knows about how that goes?))

referring to the image above :

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.

Edited by John Dolva
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Do I understand correctly that the image through the viewfinder travels through a separate lens to the one that projects an image onto the film without ANY opening between the two?

Yes, You perfectly understood! :)

This camera doesn't have a real reflex viewfinder.

The axis of the main lens and the axis of the viewfinder are parallel but they are shifted vertically of a few centimeters

(almost two inches).

B&H-02.jpg

Edited by Marcel Dehaeseleer
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(well there goes my attachment quota, I'll see about getting more (anyone knows about how that goes?))

John,

When I had that happen to me - I just went back and deleted some of my older attachments and that allowed me to add new ones. I hope that helps.

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(well there goes my attachment quota, I'll see about getting more (anyone knows about how that goes?))

John,

When I had that happen to me - I just went back and deleted some of my older attachments and that allowed me to add new ones. I hope that helps.

Yes thank you Bill, it works. Thank you Marcel, and Lee and Frank, and thank's for various encouragements. I've decided to continue this thread now in Limousine stopped? topic. This one's interesting to me though as a part of an overall experience of mine with regards to dealing with the research community which prior to this I had very little of. I'm primarily an 'artist', while I have a little experience in maths/physics (2'nd year uni many years ago) I have mostly been rambling around australia just living life. So to turn my mind to what seems like such a simple problem has not been easy. I'm not convinced yet that this approach will turn out useful nor that my reasoning is entirely correct.

However input is what I'm after so there it is.

*on a side note, I have my own ideas regarding editing of post's. Correcting obviously silly mistakes, fine, correcting because developments has led one to understand things differently from the thinking of the original post, or because a member has pointed out that error I think should be done separately, leaving the original intact. I'll ask John and others but I've asked on procedure / methodology previously with little response so prob. It gets a bit confusing when going back to a thread to find someone has altered a post without pointing out that alteration.

John

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