Clever people, these Russians...
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Razor, the camera doesnt have to run at the same fps as the rpm of the rotors, the rpm just has to be a multiple of it (eg 30 fps but an rpm of 300 means that the rotors appear in the same position on every frame but have in fact rotated ten times between the frames)
Hilarious to read some of the posts below that video though!!!
Hilarious to read some of the posts below that video though!!!
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Thanks for clearing that up.
It annoys me when people's first reaction to a lot of aviation videos is "That's Fake".
I feel like replying to them personally but can't be a%sed.
It annoys me when people's first reaction to a lot of aviation videos is "That's Fake".
I feel like replying to them personally but can't be a%sed.
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Razor61,
It's a bit like using a strobe flash to "stop" motion, e.g., a running engine.
With video it's only coincidence when there is a such a near-perfect match between rotation and frames-per-second.
But I do remember a BBMF Lancaster "four-engine-out" flypast with the props seemingly windmilling very slowly....
With todays very high shutter speeds, it can become a nuisance on aircraft photos as well, when the props are perfectly "frozen".
It's a bit like using a strobe flash to "stop" motion, e.g., a running engine.
With video it's only coincidence when there is a such a near-perfect match between rotation and frames-per-second.
But I do remember a BBMF Lancaster "four-engine-out" flypast with the props seemingly windmilling very slowly....
With todays very high shutter speeds, it can become a nuisance on aircraft photos as well, when the props are perfectly "frozen".
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Razor, the camera doesnt have to run at the same fps as the rpm of the rotors, the rpm just has to be a multiple of it (eg 30 fps but an rpm of 300 means that the rotors appear in the same position on every frame but have in fact rotated ten times between the frames)
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If you watch carefully, the rotor steadily moves back and forwards a few degrees throughout the display, so the rotor speed is probably varying, although, as said, it depends on multiples of frame speed, so if, for example, 25 frames per second, and it increases by 100 RPM, then slight rotor movement during transition to new RPM
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That's all very well, but it would mean that the rotor speed remained constant through out the entire display, is that likely?
It's indeed the blade pitch that is varied "cyclically" for pitch and roll control and "collectively" to go "up and down", not rotor rpm.
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MightyGem,
That's a PERFECT one.....
It makes one suspect that rotor rpm can be set to some pretty exact round figure (say 300 or 350 rpm) which then exactly matches the 25/50 fps rate of the camera.
That's a PERFECT one.....
It makes one suspect that rotor rpm can be set to some pretty exact round figure (say 300 or 350 rpm) which then exactly matches the 25/50 fps rate of the camera.
