The Newans were clearly a valuable photo op and have been on the ground long enough for a crowd of photographers to gather, the other hint is that Umbrella Man and his mate are finally sitting and just appear bored.
Here's another photo of the Newmans who now appear relaxed and long after the photographers have moved on and we can still see no one running anywhere the classic knoll fence.
Ironically the only self serving time guestimate of what you claimed as "seconds" came from you. LOL!
But it doesn't really matter anyway because the photographic evidence that you just conveniently ignored clearly shows the first people who moved anywhere, moved right past the grassy knoll fence.
The Bell film shows a whole lot of people have arrived at the crime scene and nobody is running anywhere near the grassy knoll fence.
JohnM
Agreed. Clearly, the people are trying to see the limousine. A lot of people did not clearly see what happened to the President. For most, someone?s head was in the way of their view of the limousine at z312, since most viewers were to the northeast of the President, not standing alongside. Most would have difficulty seeing the limousine at all and didn?t realize that it was leaving the plaza at high speed after z345. So, they tried to go far enough to the southwest in hopes they could see the limousine and hopefully find out that President was not wounded. When they saw the limousine was no longer in the plaza, they headed for the overpass in hopes of seeing the limousine just on the other side, not realizing that the limousine immediately headed off at high speed for the hospital.
The real ?Rush for the Knoll? did not occur until a couple of minutes later, when it occurred to the people that since shots were fired, it would be prudent to get out of open spaces. For many people, the fastest way to get away from open spaces was to cross Elm Street, go up the grassy knoll and get some protection on the other side of the fences and monument.