General Discussion
In reply to the discussion: GHW Bush, JFK's assassination, the CIA and drugs [View all]coalition_unwilling
(14,180 posts)as is possible with the Zapruder frames 312-313, your friend would probably have been able to measure first a perceptible movement of the head forward before the head jerked backward, exactly like JFK's head moves in Z312-313. The reason it is not apparent to the naked eye watching the Zapruder film in motion has to do with the fact that Zapruder's camera filmed at 18 frames/second but the head movement forward occurs within 1/18 of a second before the recoil backwards.
This among other things is yet another reason why eyewitness testimony is often not the most reliable testimony (a dark secret among defense and prosecuting attorneys) . . . b/c the eye can and does play tricks on us and is not the most accurate recorder of reality at all times.