Jump to content
The Education Forum
  • Announcements

    • Evan Burton

      OPEN REGISTRATION BY EMAIL ONLY !!! PLEASE CLICK ON THIS TITLE FOR INFORMATION REQUIRED FOR REGISTRATION!:   06/03/2017

      We have 5 requirements for registration: 1.Sign up with your real name. (This will be your Username) 2.A valid email address 3.Your agreement to the Terms of Use, seen here: http://educationforum.ipbhost.com/index.php?showtopic=21403. 4. Your photo for use as an avatar  5.. A brief biography. We will post these for you, and send you your password. We cannot approve membership until we receive these. If you are interested, please send an email to: edforumbusiness@outlook.com We look forward to having you as a part of the Forum! Sincerely, The Education Forum Team

Chris Bristow

Members
  • Content count

    80
  • Joined

  • Last visited

Everything posted by Chris Bristow

  1. Since John Costella put forth his theory about the lack of pincushion distortion in the Stemmons sign there has been only one counter claim refuting his theory. That is the leaning/swinging pole explanation and it really threw a monkey wrench into the matter. In trying to find a way to test the swinging pole theory I noticed a basic rule of perspective that seems to completely disqualify the leaning/swinging pole explanation. It is true that a leaning pole will appear to change its angle as perspective changes(As the camera panned), but the simple rule is a pole leaning AWAY from the observer will swing WITH the observers motion. Conversely a pole that leans TOWARD the observer will swing AGAINST the observers motion. The Stemmons signs right pole leaned AWAY from Zapruder and he panned to the right. This means the pole could only swing to the right but the motion in the comparison of frames 193 and 228 shows the pole swung to the left. This makes the swinging pole theory impossible. A quick way to test the rule is hold two pens, one straight up in your fist(for a reference point) and lean a second pen between your index and ring finger. Hold it out in from of you and lean from side to side, then lean it towards you and do the same. You will clearly see the two opposing motions. I have heard people express doubt about Zapruder panning only 6 inches or so and causing a full 2 degree change in the poles angle. I tested this on a small scale and full scale. I leaned a pole at a full 6 degrees(Per the Bothum photo which was taken from a position perpendicular to the direction the pole was leaning) and standing 50 feet from the pole I panned almost 8 inches and achieved only about 1/8 to 1/4 of a a degree of change. To achieve a full 2 degree swing I had to walk about 11 feet!! How did Zapruder do it panning only 6 inches from frame 193 to 228? I have heard no other counter claim refuting Dr Costella's claim since it was first made public roughly seven years ago. Are there any other explanations or is there a flaw in my observation? Thanks
  2. A QUESTION ABOUT THE DANIELS FILM.

    Thanks Michael.
  3. At the end of the Daniels film the camera points down and we see the shadow of two cars passing by. The first shadow of the front right corner seems to show Curry's car pass by first, then what is obviously the Queen Mary with it's flag mount on the bumper is second. Curry and others testified that the limo never took the lead and both the Daniel film and the McIntyre photo show the Queen Mary right on the limos rear bumper a moment before we see the shadows pass by. I am wondering if the Daniel film was cut and put back together in the wrong order but the images are to dark to see if there is a cut.
  4. Three Tramps.

    Thanks Ron, it could have been the Pullman's and the story morphed into a boxcar cause that's where tramps are expected to be.
  5. Three Tramps.

    Where was the "boxcar" that the tramps were found in? The Hughes film gives a good view of the yard and shows 3 pullman cars. Were they supposed to be behind the other cars?
  6. Alberto, I just want to point out one thing here. These photos were made at about 12 feet and the angle is around 12 degrees. The two photos are aligned at the trigger. Notice how from the trigger down the leaning rifle is much longer, but above the trigger it is only slightly longer. That is lot of distortion. (You will have to click on it to see the lower part, sorry.) I made a mistake is setting up this photo. I made the distance from the camera match at the top of the barrel instead of the middle point of their length. So the top portion of the stock on the leaning rifle is closer to camera and so also slightly enlarged. Had I done this correctly it would have been smaller than the butt of the rifle. So the only point I can make is that the butt of the gun has become much larger than the top half.
  7. Ray, yes the enlarged portion of the rifle tappers off as you move up but includes some the scope. The smaller scope is in the OP photos but not in my comparison. That is because my leaning rifle has not been resized. If I shrunk the leaning one to match the size of the other rifle the scope would also shrink. My comparison only illustrates the increase in size of the butt end. the proofs can be measured in the OP's original photo comparison. I messed up when I made the photos and cut off the end of the barrel. I have to use the end of the stock to see the shrinking of the barrel end of the gun. The butt ends are visible if you click on it
  8. To see this photo in full you may have to click on it then click again to pause. The butt of the rifle is the issue but it is cutoff. Thanks Here is an interesting result I got from leaning a rifle at about 10 degrees(same rifle in both images). Not looking for pinpoint accuracy here, just making a point about image distortion when the camera is close to the subject. I photoshopped them to align at the triggers. The upper part of the rifle is doing what is expected, it is just a little smaller than the straight image. But the bottom of the rifle on the left has increased in length dramatically. The top has gotten smaller and the bottom has become bigger because percentage wise it is much closer to the camera. If the rifle had been forty feet away the lower part would only be slightly closer and the distortion would be next to nothing. It is the proximity to the camera that is the culprit. This creates a problem when you compensate for the reduced vertical dimension of the leaning rifle. If the rifle was 40 ft from the camera you could just resize the vertical to correct the length of the rifle. But if you try to resize a distorted picture like the rifle on the left you will only make a larger distorted image. Resizing the vertical image is done in a proportional way so it will not correct the large lower portion. Resizing a leaning object to it's original length will work as long as the image was not distorted by its proximity to the camera. If you then try and resize either rifle so the lengths match for comparison more problems become evident. First the bigger rifle butt is longer and when aligned at the bottom the larger butt displaces the scope forward. That is most of the reason the scope does not line up at the rear. Oh ya couldn't find the scope, that is a zero power paper roll tube. There is also a tricky third distortion problem. After increasing the length to compensate for the rifle leaning away from the camera you still have a rifle that is a bit too long due to the longer butt. This means when you go to match the length of the two images the distorted image will start off larger than it should be. This means it can't be enlarged to its real size(In Comparison to the other rifle) and parts other than the oversized butt will end up looking small in comparison. The proof is the parts will be smaller in BOTH the vertical and horizontal because the image could not be enlarged fully. If you look at the comparison that is the subject of this thread you will find the eyepiece on the scope is not only shorter it is about 12% smaller in height too! Conversley if you measure the relative sizes of the butt you will find the opposite. The butt of the gun in the image taken in front of the TSBD is larger in every dimension, yet the scope on that same image is smaller in both dimensions.This means the scope is smaller only because it is a smaller image. So I think this strange mismatch in the leaning rifle with the larger butt and smaller scope occurring in both the vertical and horizontal is strong evidence that this is just a case of photographic distortion.
  9. Paul, if the story was that "the others got away." that would result in an extensive investigation into the other shooters present in the plaza. That could lead to the identity of the real shooters. It seems odd to me that their plan would allow loose ends like that. I'm sure you considered this already, what do you think of the issue?
  10. David Lifton has mentioned the limo stopping somewhere around the underpass. This raises a question I have that someone may have some input on. At the end of the Jack Daniel film, after the limo passes, we see the camera tilt down and then see the front bumper of two more vehicles pass by. The first one may be Curries car but the 2nd one is the Cadillac SS follow up car identified by it flag post on the front bumper. So does it seem odd that the SS Cadillac would allow any car in between it and the limo?
  11. Altgens 6, a different view

    Bill, that pasture slope is something I have wondered about. You can see it but measuring it is not easy. Luckily nothing I have studied so far required it. I have noticed in street repaving they added a few layers over the old ones, then after several of those they took out all the layers and started at the bottom again. So maybe the difference depends on when it is measured.
  12. Altgens 6, a different view

    Bill ya 3 or 4, they say 4 degrees but I have not checked it myself. I assumed the curb was about 6 inches high and I would add one or two more for the carpet of grass. I have heard the street level has risen several inches due to resurfacing over the years and the crown of the street would raise him several inches if he really was 6 feet into the street. Lots of little unknowns but he definitely was 2 to 6 feet into the street in A. 6. Too bad Google Earth can't takes us off the street and onto the grass and other spots. A 3d Dealey plaza we could walk through would be great.
  13. Altgens 6, a different view

    Bill, the limo also drops about 9 feet in altitude from Altgens 6 to 7, from No later than Z255 to z390(approx.). That is the main reason we see the trunk being lower in A. 7. The curb must add about 6 inches to the perspective also. The time between A, 6 and 7 should be about 8 seconds if From Z255 to Z390. Frame 390 is my best estimate based on a LOS from the middle of the spare tire cover to the lamppost behind it.
  14. Altgens 6, a different view

    John you are 100% wrong on this one. The signs should not show up behind the limo. Please just take an unbiased look at the overhead map I provided on page 13. Just look at the red lines representing Zapruders field of view and line of sight vs Altgens. I have laid them both out and you should be able to see very clearly that Zapruder could see the signs but Altgens was far from Zapruders position . Zapruder was looking from almost behind the sign and Altgens was so far to the right of Zapruder that he did not have the signs in his line of sight. Lets sort this out. Look at the map and tell me what is incorrect with the LOS laid out for both men. If you cannot find a mistake then you may have to consider the maps as accurate. The maps are proof that the signs should not be visible in A 6. If you can prove otherwise please demonstrate it with a map.
  15. Altgens 6, a different view

    If you want to know the actual position of the limo in Altgens 6 you can plot the line of sight from the two ends of the lane marker with the background. Every plot point lines up with Z255. No other lane marker will line up! Once you have determined which lane marker it matches on the WC survey map you can place the limo there and line up plot point behind it. If anyone considers the photos doctored then all bets are off and there is no reason to try and find its location. But as it stands Altgens 6 is a perfect match for Z 255. There are certain theories that fall apart when you confirm Z255 for A. 6. For instance the Willis girls arms reflected in the front right 1/4 panel are out to her side but in Z222 (approx.) they are not. But once you know the Z image of her comes some 33+ frames before the reflection in the limo, the issue is moot. I posted a map on page 13 that should prove A. 6 = z255. Depth of field, aperture and focus will not change the plot points. If there is a mistake in my map please point it out, but if there is no mistake then the map should resolve the question of which Z frame matches A. 6. Note: I tried to match the survey map lane marker with old photos and it seems to match well. But plotting Altgens position with the lane marker moves him about 3 feet south, closer to the curb. I wonder if anyone knows how the survey determined how far into the street Altgens stepped for A. 6.?
  16. MOORMAN AND MOTION BLUR

    Does anyone know the shutter speed of Mary Moorman's polaroid? I thought she was at 1/50th and Zapruder at 1/40th. I'm asking because I don't see any motion blur from the limo or the background in the Moorman photo. Zapruder shows much more motion blur at 313 and he was far from the limo. Moorman was right next to it and had to pan much faster than Zapruder. It is if the limo was barely moving or stopped, imagine that.
  17. MOORMAN AND MOTION BLUR

    Sandy, I thought the auto focus may add a bit to the overall focus. I have noticed many times that double images appear where I expect blur. Like many frames of the Stemmons sign poles. Brighter images or things at varying distances may have something to do with why some images blur and others double, but it is weird. Your hypothesis has to do with something other than missing frames or matte work on the limo?
  18. Altgens 6, a different view

    Ok I have not looked close at the Moorman shoes issue but the 2 photos of Moorman's shoes, second from the top on the right, doesn't that right shoe look way way too long? And the tongue is almost down by her toes.
  19. MOORMAN AND MOTION BLUR

    Whenever the limo has no motion blur the camera was not unsteady or it jiggled just right. Either way we can determine the motion blur in those frames because the witness' will show all the blur caused by following the limo. Sandy I don't know if Zapruder had auto focus back then but maybe it shifted a bit from 308 to 309.
  20. MOORMAN AND MOTION BLUR

    Alistair, I know the wider the aperture the more spherical aberration and the focus softens. That should cause an overall blurring and turn round objects into oval ones. I would guess lengthening the depth of field would soften the focus in other ways too but not sure about how that would work. The difference with motion/panning blur in this case is that horizontal line of blur that denotes the motion. As far as the difference between still photography and motion the only real difference I can think of is the shutter and aperture, otherwise each frame is like a still photo. At least nothing that will affect the motion blur that I can think of. Would like to hear an expert weigh in on it though.
  21. MOORMAN AND MOTION BLUR

    Bingo, thanks Alistair. It says "Shutter: 2-speed everset rotary-leaf design; 1/25 and 1/100 plus Bulb". I assume plus bulb means 1/100 with the flash working. So hers was even slower than Zapruders and still blurred less.
  22. Altgens 6, a different view

    John you said "If one looks at the photo the light pole aligns more with the rear of the Secret Service vehicle rather than the presidential limousine then 8 feet stretches to 40?" You are talking about what is next to the lightpost? I am talking about the Altgens LOS. Yes the lamppost is closer to the SS car but that is not the LOS we are using to plot positions. "From Altgens position in the Elm St. roadway then both the freeway signs and the SW corner of Elm St. should be shown. 8 feet stretches to 20 feet because we see the light pole and the limousine but not the signs? " The sign is not visible simply because it is out the frame of the camera. Maybe that is a crop but I am just saying the signs are not there because they are beyond the lamppost. Do you use the overhead map when plotting? Here is a map showing Altgens and Zapruders view in 255 and Zapruders view at 225. The green lines represent Zapruder at 225 and the two sets of red lines represent Z and A at 255. The Stemmons and Thornton signs are in the red boxes. This map should make it clear that Altgens should not see either sign. So maybe the photos have been changed but the missing signs are normal, we should not see them from Altgens LOS. The lamppost is the green dot just below the red arrow
  23. MOORMAN AND MOTION BLUR

    Thanks Bill, Zapruder was 18 fps but the shutter speed was 1/40 I believe. That determines the amount of motion blur. You said the car was barley moving in Moorman's photo but Zapruder 313 is the same moment in time or very close, so the limo speed must be the same in both Zapruder and Moorman. I was looking at the side of the white wall to determine motion blur which looks pretty sharp, So I am wondering about the shutter speed of Moorman's camera
  24. Altgens 6, a different view

    In Altgens 6 you can see a lamppost above/behind the limo's right headlight. If you look on the survey map(below) of Dealey that lamppost is about 8 feet East of the Thornton sign and so the sign is out of frame. That is why both signs are not in the photo. A clean way to verify if it matches frame 255 is to draw 2 lines of sight using the white lane marker near the limos right front tire. First note the background directly above the two ends of the lane marker(Which are the right edge of the white pillar and the entrance to the TSBD.) then use the overhead survey map to draw a line from the markers to the background objects, then extend those lines down and they will meet at Altgens position(in the street) on the map. That will allow you to determine which lane marker is in the photo and therefore the location of the limo . If you want to double check it do a line of sight for the limo's right headlight and the lamppost above it. Both methods will verify the limo at the 255 position. One thing about Altgens LOS is plotting it puts him several feet closer to the curb than the map shows. I was very careful in the plotting and wonder if anyone else would like to plot it and test my results. If you use the maps location for Altgens the LOS swings more than 8 feet across the TBSD from what I plotted. So it is not a matter of a slight error.
  25. Backyard Photos, invitation for Jack White.

    Sandy, that clears it up and the rifle shadow issue looks very interesting. Once I accept something like this I still put a critical eye to it cause I can be fooled by my eye, but it looks like a solid claim. If you have anything specific you can relate about what was told you about distortion causing the fence to lean, let me know. I would like to sort out that issue. Strange, I though it was a different post of yours I was responding to. Thanks for the extra info on the distortion guys views.
×