probably not new but neat nonetheless.

[dooom]

Enjoy!

 

jQDjJRYmeWg

 

hind majically flying. I wonder if we secured the right FPS of the game playback this could be repeated?

[EtherealN]

Probably not, since rotor RPM is variable. But if you managed to make a script that uses LUA-export to collect the rotor RPM and pass that on to the FPS setting then maybe - but that would only work if that setting can actually be changed on-the-fly which I don't think is possible.

[Spieler07]

More of this:

Ka-52 http://video.yandex.ru/users/surgeon4/view/2/

 

Ka-50 http://video.yandex.ru/users/surgeon4/view/1/?cauthor=surgeon4&cid=1

Enjoy!

[Boulund]

Probably not, since rotor RPM is variable. But if you managed to make a script that uses LUA-export to collect the rotor RPM and pass that on to the FPS setting then maybe - but that would only work if that setting can actually be changed on-the-fly which I don't think is possible.

 

Isn't rotor rpm actually quite stable? I thought only it was changes in blade angles that increased or decreased lift. At least in the Ka-50?

[AlphaOneSix]

Rotor RPM tends to be variable within a small range. Unless of course you're playing DCS, in which case the rotor RPM tends to be highly variable because people abuse the aircraft more. The only time the rotor RPM will really change is during pitch changes. The pitch of the blades change (increase, for example) and they will want to slow down, so the engines provide more power to keep the rotor RPM stable, but the engines can't act instantaneously, so there is a slight lag where you get rotor droop (a droop in RPM, not the blades themselves).

[EtherealN]

Yeah Boulund, but not quite stable enough for creating that illusion through fixing FPS, I believe, unless you are able to do it dynamically, because the smallest of tiny drifts will immediately spoil the illusion.

[Kenetic]

It's the speed of the camera filming it, is it not?

 

I really don't know much about photography, but the blades are spinning faster than the camera can film, or something like that.

[EtherealN]

Yes, a video camera actually does not capture "video" as in "moving pictures", rather it's a lot of still photographs. If you get the right ratio between the speed at which the camera captures the photos (and a quick enough pickup on each still) you can end up with the rotors being in more or less the same position every time.

[AlphaOneSix]

The Mi-24 has a very convenient rotor RPM: 4 revolutions per second (240rpm). If the frame rate of the video is only 4 frames per second, then *BAM* motionless rotor blades.

 

The Ka-50 rotor RPM is 257 (I'm pretty sure, anyway).

[Boulund]

Simple as that =)

It shouldn't be incredibly hard to produce a Ka-50 vid where the blades look like that are seated perfectly still I think. If you capture a film with a high frame rate and in post processing cut out all intermediate frames where the blades are in the wrong position. IMHO the small rpm-changes during pitch angle changes would be very minute and easily fixed in the end.

But of course, if the rotor RPM is indeed 257 it would be hard to capture it directly at "fixed position". =)

It still looks very cool though ;)

 

Just thinking of how big the changes in rpm are when adjusting angles or heavy manouvering. It couldn't be more than tops 0.5s lag in engine response? Then maybe we could observe maybe 1.5-2.0s delay until rpm is restored fully (just making numbers up, if you know, please correct =)). How large could the drop be? I seriously have no idea but let's assume say 5%, that would be 244 rpm directly after that 0.5 lag (we've now taken two frames with the rotors in their incorrect position). Within the 2.0s time to get back to nominal rpm we've managed to capture 16-20 frames with the blades in incorrect position, but just how far away from their correct position where they? I think that the small change in rpm might displace the rotors a little bit, but not entirely enough to ruin the illusion of stationary rotors, especially from a distance. I'll see if I can't think a bit about this next time I get to sit down for a while =)