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# THE STEMMONS SIGN AND PINCUSHION DISTORTION

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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

Edited by Chris Bristow
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