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Chris Bristow

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  1. Chris Bristow

    Backyard Photographs

    I have a new method for measuring the backyard. On google Earth you can count the horizontal slats on the front of the house and compare them to the 80 inch screen doors. I count 32 slats which equals 80 inches or 2.5 inches per slat. From a side view of the house that shows the landing in the backyard I used the slats to confirm that the landing is 10 feet high, maybe 10 ' 4" at the tallest. I have also confirmed the landing at 10 feet two other ways. So that makes the steps 8 inches tall each. Oswald's head comes to 1.1/2 inches below the top of the 9th step. That puts him at 5'10. But the first step seems to be short by about two inches which makes Oswald 5'8". I have found that when you do not stand perfectly straight to measure your height your slouch drops one to two inches off your actual height. Also I have tested his lean and found it takes another inch off. I get his height at 5' 6" which is about right when you subtract his slouch and lean.
  2. Chris Bristow

    Backyard Photographs

    Tom I am looking over your work in progress. It is gonna take some time to digest it. One thing about Oswald's lean is I have seen no one duplicate it. I have been trying to determine the angle of his hips and they are almost straight forward, maybe 8 degrees of angle. If a person is aloud to angle their right hip back 30 to 40 degrees and turn the right foot out way past Oswald's, it really blows the test. When a person can turn the right leg and hip way out it allows them to rock up onto the right knee and lean over that locked right knee. This allows them to lean 3 to 4 degrees more. If they turn way out and can also hyper extend the femur they gain more degrees of lean. So it is crucial that the position of Oswald's right foot and hips is maintained. I find that if you keep the foot and hips correct the posture becomes impossible. If you just try to line up your right foot under the right knee and belly button while maintaining hip and foot angles it is a fail. You can even cheat a bit go one inch right of the belly button and turn the hips back up to 20 degrees, but I think you will find you are still several degrees short of the goal when you fall over.
  3. Chris Bristow

    Backyard Photographs

    Tom, how do you determine how much keystone there is and did you use a program or tilt the image?
  4. Chris Bristow

    Backyard Photographs

    Michael I think so. The floodlight illustrates a good point. it is all about perspective and as you say you have to apply it to life on earth. Shadows are not light and do not have to move in the same direction as the light. Simply take anything and let it cast a shadow on the wall, now tilt it all around and watch how far you can alter that shadows direction. Even that crazy shadow behind the background makes perfect geometrical sense.
  5. Chris Bristow

    Backyard Photographs

    John, Fantastical reasoning, really? I am using the optics I have studied for 30 years. I have been determining angles, shadows, reflection and more because it has a lot to do with how to troubleshoot optical problems people have with eyeglasses. I have passed the state boards and studied further. One of the questions on the advanced test asks you to calculate the length of a shadow based on the persons height and distance from the light source. That seems to drift away from eyeglasses a bit but the test is very comprehensive. So I am very confident that minus the occasional mistake old farts make, the methods I use are rational. It is a common mistake to think all shadows must behave as you say. It may seem so intuitive to you that you never look beyond to test your belief. Even that crazy shadow behind and below the landing at the top of the stairs is completely normal. If you really want to get past this incorrect concept we could discuss that crazy shadow, and if you are willing to take a piece of paper and stand under a light for a minute we could unpack this whole thing.
  6. Chris Bristow

    Backyard Photographs

    I think the post is a 4x4 which is really 3.25 inches. The post shows us the front and side so it is more than 3.25, but you can see the corner and then use the front measurement as a gauge. I get 13 inches for the newspaper and that leave me short by about 2.50 inches. But I found if i stand normal, not totally straight like when we measure our height, it reduces my height by 2 to 2.50 inches. So his height seems correct.
  7. I am not weighing in on the validity of the chin controversy but after looking closely at the Dartmouth study I found some problems that may be of interest to anyone investigating their study. The first problem is not obvious because they have placed the mug shot and backyard images on top of each other. They appear to match in size if you compare the width from ear to ear. But because the backyard image is looking very slightly to his left the ear measurement becomes worthless. If you place them side by side you find the eye to mouth measurement is at least 11% larger in the mug shot. The backyard image is looking downward about 6 degrees more than the mug shot, but this does not cause the backyard eye to mouth measurement to shrink and does not affect the comparison. (I learned something very non intuitive about this perspective change of tilting the head down. The first 40 degrees of tilt down cause the eye to lip measurement to actually increase a tiny bit instead of shrinking as I assumed. That was a surprise! It turns out as you tilt down you start to see that the eye is farther back on the head than the lips. When the person is facing straight forward you can't measure the fact that the eye sits farther back than the lips. But as you tilt your head down that difference starts to become visible and measurable. I guess portrait artists already know this but it was a new and interesting aspect of perspective for me.) The second problem is that the backyard image is looking down about 8 degrees more than the mug shot, but when they created the model they more than doubled the amount of tilt. When you place the model next to the image you find the height of the lighted area on Oswald's chin is smaller in the model. However before you can measure this you have to make the correction explained in the next paragraph 'Problem 3". Problem 3 is that both computer models are oversized by 6%. Before you make any measurements you will have to shrink the computer models by 6%. The backyard image is tricky when making this comparison because since it is tilted down more than the photo the dimensions will gradually shrink as you go from top of the face to the bottom. One last small issue is the model of the mug shot is straight up and down while the mug shot itself leans to the right by 4 degrees. The backyard image is rotated maybe 1 degree more than the mug shot. So for the best comparisons you should rotate all the images to a vertical alignment. Both the larger mug shot and the extra rotation downward of the backyard model create a bias in favor of the results they obtained. They both cause the light on the chin to shrink and so the light does not wrap around the side of the jaw as much when the too small model is compared with the oversized mug shot. I tried to resize things and photo shop the corrected chin size onto the mug shot. But because the shadowing on the two images is different it did not blend well. To be fair I did notice the increased size was not very significant but for anyone studying the images I think the information above should be helpful.
  8. Chris Bristow

    Backyard Photographs

    I just did some photographic testing on this post shadow vs Oswald shadow a couple weeks ago. Ray is correct and if need be i might do a video so i can move to different positions and you can all watch as shadows change. But I like thought experiments so try the following one which logically proves rays point. 1. picture yourself standing with the Sun directly at your back and the post directly in front of you. This means the Sun, you and the post are all on the same line of sight. So where is the post's shadow when you are in a direct line with it and the Sun? The answer is the shadow would be hidden directly behind the post. That is pretty easy to visualize and if you agree with me you can consider point 2. 2.Now if you understand that you, the Sun and the pole all have to share the same line of sight in order to hide the shadow behind the post, then consider that Oswald's position in the picture does not share that same line of sight. Oswald is not in direct line and so could never have his shadow hidden directly behind him as the post does. So if Marina was 10 feet away then Oswald is 7 degrees of to the right of the pole and we should see his shadow protruding by the same 7 degrees. But oswald is also leaning and that adds another 7 degrees. Then you add the perspective change of a camera at ten feet and approx 4 feet high and 14 degrees of shadow expands 2 1/2 times to about 35 degrees. (The post shadow is not subject to the same distortion because as the perspective changes vertical lines just shrink in size while angled lines change their angle towards the horizontal). Although I can account for what should be 14 degrees of original shadow distorted by perspective to 35 degrees, Oswald's shadow is closer to 50 degrees. Still can't explain that. It would take 20 degrees of shadow angle for the perspective to change it to 50(20 x 2.5 = 50)
  9. Chris Bristow

    McIntyre Photo Ellis or Bellah?

    John yes they would slow down for the turn but they could easily take it at forty mph. But at forty the middle guy would fall back just a bit. I swear they all have a grin on their faces too. At their apparent speed they would get run over in about 5 seconds if they don't step on it. Very strange thing. By this time there had been several radio calls saying "shots fired go to Parkland. So these guys had to know what was happening by that point. If Ellis is correct in his recollection the Altgens 7 is a lie. Although it appeared in a newspaper headline with 24 hours so not easy to explain as a fraud.
  10. Chris Bristow

    McIntyre Photo Ellis or Bellah?

    Thanks Denis, I have heard these but the quality is much better
  11. Chris Bristow

    Backyard Photographs

    The math is simple and proves the shadow on the post moves as it should. The telephone lines can be no closer that 14 feet and at that distance they should move just like we see in the 3 photos. If the lines are beyond 14 feet then the shadow would move even faster. The math does not lie and I think we have to accept that the power lines can be no closer than 14 feet and from that we know mathematically that the shadow would move 3 to 5 inches in only 10 minutes. To find how many inches a shadow moves per degree of the Sun's elevation you take the 14 feet x 2= the diameter x 3.14 to get the circumference then divide 360 degrees by the circumference and you get how many degrees equals 1 foot movement which is 360 / 88 = 3.9. That is one foot movement for every 3.9 degree elevation change. The sun's elevation was decreasing by 1 or 1.6 degrees every 10 minutes. (can't remember my exact figures) so the shadow had to be moving at LEAST 3 to 5 inches up the post if the time between photos was up to ten minutes. So because the power lines can be no closer than 14 feet from the post the shadow would move no slower than 3 inches every ten minutes. On another topic, I too have wondered about the shadow you pointed out recently as going in the wrong direction(It is the shadow leaning upward to the right that sits on the wall just beyond and below the landing at the top of the staircase). I think I know its origin now. It is the shadow of the South edge of the landing. I modeled it with a couple pieces of paper, one to represent the horizontal landing and the other to represent the vertical wall the shadow falls on. Once you get your light source at the right elevation and angle off or azimuth, you can reproduce the shadow and its angle exactly. Not saying these photos are real, just saying many of the theories don't hold water.
  12. Chris Bristow

    Backyard Photographs

    Recently I looked at the power line shadows on the post. The reason it moves differently is because the power lines are about 14 feet away and so the shadows move very fast. Based on the distance to the power lines the shadow should move about 6 inches over about 7 minutes.(that is from memory). If you take that 14 feet as the radius x 2 x 3.14 divided into 360 you get one foot of shadow movement for every 4 degrees change in elevation. The Sun's elevation was changing by one degree every 10 minutes so as I recall, the shadow on the post moved about 6 inches so the time elapse for 3 photos is about 5 minutes. Also the telephone lines ran down the East side of the ally right next to the Neeley house. they have since been moved across the ally to the power pole. You can verify this because the pole in your Neeley house photo (on the right side of the photo) is on the East side of the ally. One interesting thing I noticed is the shadow behind the post is only slightly visible so from that we can determine almost the exact azimuth as it relates to Marinas los. What is weird is Oswald is only 7 degrees to the right of the post( degrees based on a camera dist of 10 feet), yet his shadow extends at least 13 to 16 degrees out to the side(It measures as 40 degrees but a 16 degree angle from 10 feet distorts to 2 1/2 times what it really is. We should see a 7 degree difference plus one because the post shadow appearing to be one degree left of center. But we see way more than 8 degree. As far as Oswalds lean in 133 I find it impossible to duplicate. If you just try to align your right shin, knee and belt buckle(The center line of the body at the belt line) you will fall over. As long as you match the forward position of the right foot and match the hips which remain almost straight forward you will fall over.When people claim to duplicate the stance they tend to turn the foot(And therefore the knee) way out to the right. But Oswald's foot and hips are almost fully forward and if you match the hips and right foot you can't turn the knee out enough to make it work.
  13. Chris Bristow

    McIntyre Photo Ellis or Bellah?

    Denis I have had a question about this photo for some time and I wonder if Mr Ellis ever said anything that might shed some light on this. Myself and other bike riders have noted that although the limo is only a couple seconds behind the motor cops(It must be doing 50 mph) the motor cops seem to be putting along at about 25-30 mph. I say this because they are riding 3 abreast while navigating the turn onto the Stemmons. For the person in the middle this gets tricky at higher speeds and you would usually fall back a bit. But what really gets me is the middle cop, Lumpkin?, has his left hand in his lap! The rain gutter that you have to cross will definitely cause a slight deviation in you equilibrium and to take it at high speed with one hand is just a bit tricky, but sandwiched between two other bikes is gonna create the pucker factor even for experienced riders. Has he mentioned their speed maybe?
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