The tail rotor has 8 rounds per second and the movie has 30 frames per
second.
The blades of tail rotor are invisible on the movie.

It is conceivable that one could apply image processing (contrast
enhancement) to individual frames to ascertain the location of the tail
rotor in each frame. Remember it would be moving, so mostly where the
rotor was passing through it will still be background, with just a
slight shadow.

The link you gave doesn't work. I don't know if that's a link to the
film you have or to another film.

Much depends on the quality of the actual film itself. If it's film, it
should be scanned at high resolution and analysed. There are places
that can do this. However, there's no promise that you could actually
see what you need to see.

Jose
--
Quantum Mechanics is like this: God =does= play dice with the universe,
except there's no God, and there's no dice. And maybe there's no universe.
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