I see the trees swaying oddly around the copter - but I don’t know what to look for..
The other thing that struck me was about how firmly and stiffly the people approaching to the helicopter were marching. They seemed to be deliberately stepping high and firmly planting their feet. Not a natural walk across a green lawn at all. And the soldier standing at the back door seemed to take a very wide swing around to the side of it, too far it seemed, before grabbing the door and hoisting it up and closed.
It might have been real, but it sure looked funny.
It reminded me of one of the Start Wars movies (not the original trilogy) where there was a great army that was led by Natalie Portman’s character and they had that “marching in place” stiff look to them.
To my reply at 1899, and thinking about similar historic footage...
Look at Bush departing on Marine One.
https://www.youtube.com/watch?v=IrjQfl92x-U
None of that stiff “marching in place” stuff.
Trees seem to move normally in response to rotor wash.