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 September 04, 2010, 06:12:44 PM
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For the web version of this article see: As a guest, you are not allowed to view links.
Register or LoginToo often people ignore blurred frames of the Zapruder film. By recognizing the characteristics of various blurs they can obtain valuable information. In fact a blur caused by a rapidly moving object conveys more information than a clear frame. Two features on frames Z324 and Z325 show blurs. They are the partition between operator and passenger compartments and the small white object immediately above the head of President Kennedy. Viewing following frames reveals that white object as the tip of the gloved hand of Mrs. Kennedy. As a guest, you are not allowed to view links.
Register or LoginStepping from frame Z324 to Z325 shows two changes. The partition becomes clearer and the hand becomes blurrier. A closer examination shows most images on frame Z324 are blurrier than on frame Z325. Further the blurrier images show lateral streaking. These characteristics indicate movement of the camera with respect to the incoming light during exposure caused the blurring. By contrast, the movement of Mrs. Kennedy's hand by a few inches between frames Z324 and Z325 shows intrinsic motion as the cause of its increased blurriness. As a guest, you are not allowed to view links.
Register or LoginFrames Z325 and Z326 show Mrs. Kennedy is swiping her hand from the left side to the rear of the President's head. As she swings her hand, its direction of motion moves away from the plane of view and toward the line of sight. By frame Z326, Mrs. Kennedy's hand is speeding toward the camera and its motion causes less blurring. This observation illustrates another characteristic of blurs caused by moving objects. Namely the components of their velocity lying in the plane of view cause blurring. As a guest, you are not allowed to view links.
Register or LoginA lesser movement of the camera during exposure accounts for most objects becoming clearer on frame Z326. Having completed the left to rear movement, Mrs. Kennedy starts lowering her hand. This change in direction of her hand increases the downward component of its velocity. Not surprisingly more blurring accompanies the considerable downward speed of Mrs. Kennedy's hand as shown by frame Z327. As a guest, you are not allowed to view links.
Register or LoginA blur caused by a rapidly moving object enables calculation of two components of its velocity. In general the uncertainty in position due to blurring places an upper bound on the plane of view distance moved by an object during exposure. Knowing the exposure time permits calculation of the upper limit of two components of the object's velocity. This technique is especially valuable in evaluating brief motions such as Kennedy's forward and backward head snaps.
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September 08, 2010, 04:35:44 AM
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Go read the Zavada report and pay attention to his discussion of the film advance mechanism. He did not describe holding the film between a pair of optical flats during exposure. So the plane of the film was floating. Oh geeze Herbie, this just gets better and better.
Do YOU understand the SIMPLE concept of a PRESSURE PLATE? Did YOU see the mention of this device that applies PRESSURE to the film as it is EXPOSED at the film gate? That’s how roll film is kept flat in a camera HERBIE. You still do not understand that relative motion between the subject and the film causes the motion blur. For example, perfect panning of a subject produces a frame without any motion blur although the film in the camera and the subject in the limo were moving. Further the motion of the limo plays no role in the perfect panning since the subject was capable of independent movement. Of course I understand how blur is created in a photographic image, I’ve been using it to my creative advantage for over 30 years as a professional advertising photographer. What are YOUR credentials Herbie?
Beep Beep…you own bus just backed right on over you Herbie. In your “perfect” situation above you know you still missed the blur source INSIDE the limo (that would be the RAPID movement of Jackie’s hand) and of course the background blur. BTW can you prove that such a perfect pan existed…that is the pan speed matched the limo speed perfectly (limo as a blur source) and the camera was panned on the EXACT same angle as the limo was traveling (camera as a blur source)
WOW! Imagine that’s THREE sources of blur all rolled into a single image that must be DECOUPLED to accurately analyze the blur. And that mountain of an intellectual giant, Herbier and only finds two and he totally blows the first…When panning is imperfect, the motion blur depends upon the same two variables which are the motion of the film and the motion of the image regardless of whether the limo or a subject is the source. See above  , you might actually learn something. We know that you don't care a whit about my identification of the causes of motion blurs since they disallow your denials. Instead you elect to insult the readers by posting empty proclamations of victory after twice declining to critique my means of identifying the causes of the motion blurs. Well I have been victorious and you have lost big time. The one insulting the reader is you, by posting such utter nonsense. As they can still see, Herbie still does not understand the sources of blur within the Zapruder film. They ( at least the thinking ones) will also understand that uncoupling these blur sources is REQUIRED to analyze them. Herbie can’t do that. Your condescending tone encourages me to come out and play. Earlier you implied that the image from a lens set at infinity would focus upon the same plane. In reality the focal length, distance between the center of the lens and the plane at focus, depends upon the color of the light. Further color film is a composite of layers sensitive to differing colors. These considerations show your concept of focus is amateurish. This is wonderful! May I make a suggestion, learn to read. Currently you look like a silly old fool.
First of all I told you correctly that with the lens set at infinity focus and the lens stopped down to f11 and given the very small size of the film format, that the area of sharp focus (DOF) was quite large. THAT renders your very silly “focus blur” theory destroyed. Of course I also asked you to tell us how much film plane movement would be required for your silly focus shift theory to actually show an out of focus condition? Because the focus of the projected image also extends, IN FRONT of and BEHIND the film plane with a distance that varies depending on the f stop setting of the lens. So you see I said EXACTLY the opposite of what your false claim states. Herbie, you look good with your foot in your mouth.
BTW, nice google, too bad it was worthless to the subject at hand, and I don’t even think you understand it anyways. Now are you ready to discuss the transient motions of the film planes during exposures in response to more than eighteen stops and goes each second of the filming? Sure bring it on. I can’t wait to see you try and explain a floating film plane. It should be priceless.Herbert
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« Last Edit: September 08, 2010, 07:49:06 PM by Craig Lamson »
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September 08, 2010, 07:58:26 PM
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Super Member
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Go read the Zavada report and pay attention to his discussion of the film advance mechanism. He did not describe holding the film between a pair of optical flats during exposure. So the plane of the film was floating. Oh geeze Herbie, this just gets better and better.
Do YOU understand the SIMPLE concept of a PRESSURE PLATE? Did YOU see the mention of this device that applies PRESSURE to the film as it is EXPOSED at the film gate? That’s how roll film is kept flat in a camera HERBIE. The plate holds the edges of the film in place and leaves the inner surfaces free to vibrate. This arrangement eliminates the need for expensive optical flats to hold fixed all portions of the film surface.
You still do not understand that relative motion between the subject and the film causes the motion blur. For example, perfect panning of a subject produces a frame without any motion blur although the film in the camera and the subject in the limo were moving. Further the motion of the limo plays no role in the perfect panning since the subject was capable of independent movement. Of course I understand how blur is created in a photographic image, I’ve been using it to my creative advantage for over 30 years as a professional advertising photographer. What are YOUR credentials Herbie?
I have just demonstrated that my credentials are sufficient to blow away your "theory" of three absolute and simultaneous motions as the cause of motion blurs.
Beep Beep…you own bus just backed right on over you Herbie. In your “perfect” situation above you know you still missed the blur source INSIDE the limo (that would be the RAPID movement of Jackie’s hand) and of course the background blur. BTW can you prove that such a perfect pan existed…that is the pan speed matched the limo speed perfectly (limo as a blur source) and the camera was panned on the EXACT same angle as the limo was traveling (camera as a blur source)
Reading comprehension is not your forte. I said perfect panning of a subject produces. . . . I did not claim that the perfect panning produced a frame without any blur. So I could not have been speaking of a past situation such the Zapruder filming of 1963. Nor did I identify the subject as Jackie's hand instead I spoke of a singular subject that would exclude your plurality of Jackie's hand and the background.
Of course we know you understood my perfect panning scenario so now you ask me to prove the reality of a hypothetic scenario. But then again perhaps I give you more credit than you deserve.
WOW! Imagine that’s THREE sources of blur all rolled into a single image that must be DECOUPLED to accurately analyze the lens blur. And that mountain of an intellectual giant, Herbier and only finds two and he totally blows the first… In this thread, I am analyzing the motions of objects from their appearance on the film. Perhaps you should ask a child to explain how the analysis of lens differs from the analysis of motions.
When panning is imperfect, the motion blur depends upon the same two variables which are the motion of the film and the motion of the image regardless of whether the limo or a subject is the source. See above , you might actually learn something. I attribute a motion blur to the relative motion of the film and the image. So I dare you to call Galileo a .
We know that you don't care a whit about my identification of the causes of motion blurs since they disallow your denials. Instead you elect to insult the readers by posting empty proclamations of victory after twice declining to critique my means of identifying the causes of the motion blurs. Well I have been victorious and you have lost big time. The one insulting the reader is you, by posting such utter nonsense. As they can still see, Herbie still does not understand the sources of blur within the Zapruder film. They ( at least the thinking ones) will also understand that uncoupling these blur sources is REQUIRED to analyze them. Herbie can’t do that. My discussion that you continue to ignore identified the causes of the blurs.
Your condescending tone encourages me to come out and play. Earlier you implied that the image from a lens set at infinity would focus upon the same plane. In reality the focal length, distance between the center of the lens and the plane at focus, depends upon the color of the light. Further color film is a composite of layers sensitive to differing colors. These considerations show your concept of focus is amateurish. This is wonderful! May I make a suggestion, learn to read. Currently you look like a silly old fool.
First of all I told you correctly that with the lens set at infinity focus and the lens stopped down to f11 and given the very small size of the film format, that the area of sharp focus (DOF) was quite large. THAT renders your very silly “focus blur” theory destroyed. Of course I also asked you to tell us how much film plane movement would be required for your silly focus shift theory to actually show an out of focus condition? Because the focus of the projected image also extends, IN FRONT of and BEHIND the film plane with a distance that varies depending on the f stop setting of the lens. So you see I said EXACTLY the opposite of what your false claim states. Herbie, you look good with your foot in your mouth.
BTW, nice google, too bad it was worthless to the subject at hand, and I don’t even think you understand it anyways. The DOF, depth of field, measures the span of distances at which objects remain in focus. This span is not the focal length of the lens.
Opticians recognize that the focal length, the distance between the center of the lens and the point of focus, varies with the color of the light. An achromatic lens reduces but does not eliminate this variation.
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The structure of the film as a composite of layers sensitive to particular colors frustrates matching the residual chromatic aberration of the lens to the film. So in reality the camera never achieves sharp focus nor is it desirable.
Now are you ready to discuss the transient motions of the film planes during exposures in response to more than eighteen stops and goes each second of the filming? Sure bring it on. I can’t wait to see you try and explain a floating film plane. It should be priceless. The sprocket gears have considerable slop and cannot prevent buckling of the decelerating film. So when the film comes to a stop the pressure plate secures edges of the film with an uncontrolled surface shape. Further the impact of the plate against the camera body induces axial vibrations of the film. The amplitude of these vibrations depend upon the initial shape of the buckling and is an uncontrolled variable. In one case the amplitude of vibration is an insignificant mil while at another time the amplitude is a focus blur inducing tens of mils.
Herbert
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September 08, 2010, 08:21:47 PM
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Herbert,
This is extremely useful what you are presenting in this thread about blur analysis.... Frame 232 as presented in Life mag. does not have a blurred background, but should have had one if Zfilm is to be believed....in your analysis do you feel that 232 is also a smoking gun frame, as the blurred Toni Foster frame you discussis also evidence of alteration? Great stuff you are presenting here!!
Jay
They sharpened Z-232 by partial removal of the focus blur. In the early sixties the unsharp mask technique was the popular method of making a negative clearer. This technique involved producing a focus blurred copy of the negative then using this copy as a filter to subtract the focus blur from the source negative and produce a clearer negative. The technique did not reduced motion blur since production of a motion blurred filter negative was not practical at the time. Herbert
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September 08, 2010, 10:52:19 PM
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Posts: 1374
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Oh Herbie...what trash! Even with google you get it wrong. It's very clear from your post that you have zero experience in the darkroom with the unsharp masking process because once again you failed in your feeble attempt to look like you know something about the subject. BTW, never fear, I will be destroying your post above in a bit, its a bit more involved then this piece of trash by you so bear with me. So were do we start... Silly old herbie sez in the unsharp masking process you make a "copy" of the negative. BUZZZZ! Sorry wrong answer. You don't make a copy of the negative you create a POSITIVE from the negative. Poor old herbie gets it all wrong again. Have you EVER stepped foot inside a darkroom herbie? Ever made an unsharp mask? Of course not. Then silly old herbie tells us that the "copy" of negative is being created out of focus, to "subtract" some of the focus blur. BUZZZZ! Wrong again herbie! The faint and out of focus positive when sandwiched with the negative creates a "halo". This increases the local contrast at the edges of detail to give the APPEARENCE of increased sharpness. Sheesh herbie, even WITH google and someone else leading you down the path, you STILL can't get it correct. Herbert,
This is extremely useful what you are presenting in this thread about blur analysis.... Frame 232 as presented in Life mag. does not have a blurred background, but should have had one if Zfilm is to be believed....in your analysis do you feel that 232 is also a smoking gun frame, as the blurred Toni Foster frame you discussis also evidence of alteration? Great stuff you are presenting here!!
Jay
They sharpened Z-232 by partial removal of the focus blur. In the early sixties the unsharp mask technique was the popular method of making a negative clearer. This technique involved producing a focus blurred copy of the negative then using this copy as a filter to subtract the focus blur from the source negative and produce a clearer negative. The technique did not reduced motion blur since production of a motion blurred filter negative was not practical at the time. Herbert
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« Last Edit: September 09, 2010, 12:21:49 AM by Craig Lamson »
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September 09, 2010, 12:20:43 AM
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Super Member
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Go read the Zavada report and pay attention to his discussion of the film advance mechanism. He did not describe holding the film between a pair of optical flats during exposure. So the plane of the film was floating. Oh geeze Herbie, this just gets better and better.
Do YOU understand the SIMPLE concept of a PRESSURE PLATE? Did YOU see the mention of this device that applies PRESSURE to the film as it is EXPOSED at the film gate? That’s how roll film is kept flat in a camera HERBIE. The plate holds the edges of the film in place and leaves the inner surfaces free to vibrate. This arrangement eliminates the need for expensive optical flats to hold fixed all portions of the film surface.
Really? You have a CITE for that Herbie? Of course not. You like to cite Zavada, so why don’t we look to him, shall we? After all he has torn one of these bad boys down… The camera mechanism includes a negator spring motor drive which, when released by a pivotal movement of a control arm from its position (by pushing down on the start button), serves to rotate a scroll gear to drive a worm (gear). This worm serves to rotate a film footage indicator dial, and to rotate a gear carrying a crank pin to oscillate a shuttle or film pulldown claw and rotate a shutter, as well as drive a governor, and to rotate gears. The shuttle is urged by spring (pressed against the film) toward feeding engagement with the film (i.e., to engage the perforation holes) in a position between an aperture plate incorporating an exposure aperture (area) and a pressure plate (to hold the film flat and motionless during exposure). The shuttle is pivoted on a pin. The gear also carries a known disc segment type of shutter which covers the aperture during frame-by-frame feed of the film and when the camera is stopped. I know you don’t read well so let me bring it down TO YOUR LEVEL…the film is held FLAT AND MOTIONLESS. Not the herbie silly theory of the month…VIBRATING! Of course movement, even it it were happening would not guarantee a slightly out of focus frame, since the DOF at the film plane is governed by the f-stop in use at the time of exposure. In other words herbie, A frame shot with the lens wide open MIGHT show some focus shift, a frame shot with the lens at f22 would not. So we can clearly see that the very stupid stuff MADE UP FROM THIN AIR by old herbie is moronic in the extreme! Can you story shift any more.? It’s quite fun watching herbie do the backstroke.You still do not understand that relative motion between the subject and the film causes the motion blur. For example, perfect panning of a subject produces a frame without any motion blur although the film in the camera and the subject in the limo were moving. Further the motion of the limo plays no role in the perfect panning since the subject was capable of independent movement. Of course I understand how blur is created in a photographic image, I’ve been using it to my creative advantage for over 30 years as a professional advertising photographer. What are YOUR credentials Herbie?
I have just demonstrated that my credentials are sufficient to blow away your "theory" of three absolute and simultaneous motions as the cause of motion blurs.
No you have done just the opposite. You have shown you DON’T have the skillset to understand something as simple as how photographic blur is formed and the sources present in the Zapruder film. Nor have you given us any indication you have the first understanding of the photographic process nor any practical nor advanced skills in its actual use. Why is that Herbie? Because you don’t HAVE any?
So exactly WHAT are your credentials again? Simple question herbie, why not geiv us the answer….
Beep Beep…you own bus just backed right on over you Herbie. In your “perfect” situation above you know you still missed the blur source INSIDE the limo (that would be the RAPID movement of Jackie’s hand) and of course the background blur. BTW can you prove that such a perfect pan existed…that is the pan speed matched the limo speed perfectly (limo as a blur source) and the camera was panned on the EXACT same angle as the limo was traveling (camera as a blur source)
Reading comprehension is not your forte. I said perfect panning of a subject produces. . . . I did not claim that the perfect panning produced a frame without any blur. So I could not have been speaking of a past situation such the Zapruder filming of 1963. Nor did I identify the subject as Jackie's hand instead I spoke of a singular subject that would exclude your plurality of Jackie's hand and the background.
Of course we know you understood my perfect panning scenario so now you ask me to prove the reality of a hypothetic scenario. But then again perhaps I give you more credit than you deserve.
No that’s exactly what you said and we can see it if you show the more of the quote:“example, perfect panning of a subject produces a frame without any motion blur although the film in the camera and the subject in the limo were moving.”
Singular subject? Really? How quaint and oh so wrong. In the quote above you talk about the subject in the limo and a perfect pan for a moving limo. Of course you missed the background blur which we covered above but you also missed any possible blur from the subject in the limo moving independently of the limo. And lets not forget its YOU who raised the subject of Jackie’s hand. I know you have your tit firmly caught in the wringer herbie but your blatant and failed attempt at the shuck and jibe is really telling…
WOW! Imagine that’s THREE sources of blur all rolled into a single image that must be DECOUPLED to accurately analyze the lens blur. And that mountain of an intellectual giant, Herbier and only finds two and he totally blows the first…
In this thread, I am analyzing the motions of objects from their appearance on the film. Perhaps you should ask a child to explain how the analysis of lens differs from the analysis of motions.
Pardon me, I wrongly stated my phrase. If you notice I corrected it prior to your posting.
When panning is imperfect, the motion blur depends upon the same two variables which are the motion of the film and the motion of the image regardless of whether the limo or a subject is the source.
See above , you might actually learn something.
I attribute a motion blur to the relative motion of the film and the image. So I dare you to call Galileo a .
Galileo would call you a too. We are talking about the blurs in the Zapruder film which are comprised of multiple sources of movement. You have attempted and failed to properly isolate each of the blurs cause by these independent sources and uncouple them prior to your attempt to analyze them. This simple aspect of photo analysis eludes you. Where did you learn how to do this? The Jack White School of incompetence or the inside of a cereal box?
We know that you don't care a whit about my identification of the causes of motion blurs since they disallow your denials. Instead you elect to insult the readers by posting empty proclamations of victory after twice declining to critique my means of identifying the causes of the motion blurs.
Well I have been victorious and you have lost big time. The one insulting the reader is you, by posting such utter nonsense. As they can still see, Herbie still does not understand the sources of blur within the Zapruder film. They ( at least the thinking ones) will also understand that uncoupling these blur sources is REQUIRED to analyze them. Herbie can’t do that.
My discussion that you continue to ignore identified the causes of the blurs.
No it does not.
Your condescending tone encourages me to come out and play. Earlier you implied that the image from a lens set at infinity would focus upon the same plane. In reality the focal length, distance between the center of the lens and the plane at focus, depends upon the color of the light. Further color film is a composite of layers sensitive to differing colors. These considerations show your concept of focus is amateurish.
This is wonderful! May I make a suggestion, learn to read. Currently you look like a silly old fool.
First of all I told you correctly that with the lens set at infinity focus and the lens stopped down to f11 and given the very small size of the film format, that the area of sharp focus (DOF) was quite large. THAT renders your very silly “focus blur” theory destroyed. Of course I also asked you to tell us how much film plane movement would be required for your silly focus shift theory to actually show an out of focus condition? Because the focus of the projected image also extends, IN FRONT of and BEHIND the film plane with a distance that varies depending on the f stop setting of the lens. So you see I said EXACTLY the opposite of what your false claim states. Herbie, you look good with your foot in your mouth.
BTW, nice google, too bad it was worthless to the subject at hand, and I don’t even think you understand it anyways.
The DOF, depth of field, measures the span of distances at which objects remain in focus. This span is not the focal length of the lens.
That’s correct…for a change but exactly where has it been stated that focal length equals DOF. Very poor strawman herbie.
Opticians recognize that the focal length, the distance between the center of the lens and the point of focus, varies with the color of the light. An achromatic lens reduces but does not eliminate this variation.
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Wow, Herbie reads wiki! Not tell us…in actual practice…how much focus shift does the differing focus point of each color of light effect the focus of a photograph when that photo was recorded using f11? Anyways, since you won’t answer, it is just another failed herbie attempt at a strawman. BTW you ever owned an APO herbie? Ever used one? And what was the lens on the Z camera herbie and how well corrected was it for chromatic aberrations?
The structure of the film as a composite of layers sensitive to particular colors frustrates matching the residual chromatic aberration of the lens to the film. So in reality the camera never achieves sharp focus nor is it desirable.
Amazing…the camera NEVER achieves sharp focus nor is it desireable! Only from Herbie! Lets review. There MAY be some differences in focus point for different wavelengths of light. Kodachrome film has VERY thin layers, with all three layers being thinner than most monochrome films. So we have a VERY SMALL mismatch of focus points, all of which will be well covered by the DOF at the film plane. Herbie you are beyond help.
BTW I’m sure my buds will have a great laugh when they hear that its not desirable to achieve sharp focus with the megabucks equipment sitting in their equipment rooms and safes. Hey silly old herbie says so!
Now are you ready to discuss the transient motions of the film planes during exposures in response to more than eighteen stops and goes each second of the filming?
Sure bring it on. I can’t wait to see you try and explain a floating film plane. It should be priceless.
The sprocket gears have considerable slop and cannot prevent buckling of the decelerating film. So when the film comes to a stop the pressure plate secures edges of the film with an uncontrolled surface shape. Further the impact of the plate against the camera body induces axial vibrations of the film. The amplitude of these vibrations depend upon the initial shape of the buckling and is an uncontrolled variable. In one case the amplitude of vibration is an insignificant mil while at another time the amplitude is a focus blur inducing tens of mils.
This is getting rich herbie. First you go from floating film not being secured in the camera to it being secured with a pressure plate…but only by the edges. Now in a yet another lame attempt to cover your well exposed hind quarters you introduce “film vibrations” as a source of “focus blur”.
Source is a good term here herbie because you will need to supply some sources to back your claims. Your wildly waving hands do not count. In addition please supply an accurate accounting of the amount of ACTUAL “focus blur” your proposed theory represents. How quickly is this proposed vibration damped, and WHY have an open backed pressure plate ( which you still have not shown even exists.)
This is MORE than priceless stuff herbie….
Herbert
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« Last Edit: September 09, 2010, 04:07:17 PM by Craig Lamson »
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