At the instant the President stops waving and starts to lift his arm to his neck is the instant the shot came in. I can't see it happening any other way.
Thanks for the enlightenment on photo sources. It still does not explain what took place between Z202 and the movement of the umbrella man and the "Cuban" waving his arms at JFK and JC. You can see the umbrella at the front of sign not off to the back and behind.
I believe the Zapruder film first because of the many frames one after the other. Obviously this lack of synergy means something is not right - conspiracy starts with the first bullet landing! The sign is elevated and no sign of the Cuban. These guys just can't come and go - can they? There is no logical explanation! In my opinion, you can see JFK and JC both looking at them with their gaze when they emerge from behind the cover of the sign. I don't think they were staring at an empty grassy knoll. The umbrella man was very close to JFK, not off in the distant like the Willis photograph is showing.
https://www.assassinationresearch.com/zfilm/z221.jpgYou can already see the umbrella appearing at Z208. Clearly, looking at the Willis photograph and Zapruder's camera angle, it would be impossible to project part of the missing umbrella to the other side of the sign! IT IS AN IMPOSSIBILITY! https://www.assassinationresearch.com/zfilm/z208.jpgSo bear in mind, was JC left with a "sucking" wound and a collapsed lung? At Z394, he looks back from his position behind driver Greer and assesses the damage to the President! The best evidence of this look can be sign clearly in the Lightbox frames at Z394. Unfortunately these photos are not possible to put into this post for viewing. You can see his face more clearly than you can in the Costella Frames.
https://sites.google.com/site/lightboxzframes/lightbox/z350-z399https://www.assassinationresearch.com/zfilm/z394.jpgThe face can be seen more clearly in the Lightbox frame z394, just in front of the green flowers (maybe?). You can look at other frames to note that Nellie has her head tucked down by JFK's feet at this time. You can't dispute their positions and movements and the time it occurs when you review the slides together in "slide show" fashion. At the very least, he is not collapsed on her lap with her hands on his chest, his head is up! It is little wonder the Zapruder film has been held in secret for so long, it discredits so much testimony!