ADOBE AFTER EFFECTS: Forum Expressions Tutorials Creative Cloud

Slowing down Hummingbirds with Twixtor

COW Forums : Adobe After Effects

<< PREVIOUS   •   FAQ   •   VIEW ALL   •   PRINT   •   NEXT >>
Brad Weiss
Slowing down Hummingbirds with Twixtor
on Mar 22, 2012 at 2:14:58 am

So i shot some footage this summer at the cottage that i am putting together for a portfolio piece.

This footage features hummingbirds - nature's glorious hovercrafts - whipping about a bird feeder. I shot at several different angles at 59.97fps on my Canon 7D. Now that i've cut the rough sequence together, i'm using dynamic link to bring footage into AE from PPro and "ramp" the hummingbird as they feed and flit around the feeder.

My problem is this: even after converting the footage to 29.97 and putting it into its respective timeline, i still get considerable warping when the h-bird makes large movements. Even slowed down there doesnt seem to be enough frames for Twixtor to interpolate.

Does anyone have any recommends or suggestions as to correct this?



Return to posts index

Tero Ahlfors
Re: Slowing down Hummingbirds with Twixtor
on Mar 22, 2012 at 5:46:35 am

Yeah. Buy/rent a high speed camera that can shoot 1000fps or faster. Hummingbirds are too fast for 60fps.


Return to posts index

Dave LaRonde
Re: Slowing down Hummingbirds with Twixtor
on Mar 22, 2012 at 2:52:48 pm

I agree: 59.94 is still too low a frame rate to slow down a hummingbird's wings.

Even by conforming the footage to a 29.97 frame rate, which slows the shot down by a factor of two, then applying twixtor to slow it down by another factor of two, the wings would still be blurred.


There's no way to un-blur the wings because in every frame the wings are blurred.

Dave LaRonde
Sr. Promotion Producer
KCRG-TV (ABC) Cedar Rapids, IA


Return to posts index


Brad Weiss
Re: Slowing down Hummingbirds with Twixtor
on Mar 22, 2012 at 3:43:33 pm

Thanks for the quick reply guys. I know i can always count on the COW for well informed advice.

I figured this might have been the case when i first started playing with the footage. As much as i love shooting with my DSLR i realize its limitations, though im always looking to push them.

That said im still going to play around with what i have and hopefully will post a link to it soon. Would have loved to have shot the birds with a Phantom HD, but considering i was just at the cottage on vacation, the $2500/day rental price just wouldn't have been worth it.



Return to posts index

Tero Ahlfors
Re: Slowing down Hummingbirds with Twixtor
on Mar 22, 2012 at 5:07:40 pm

Check out the Casio high-speed compact camera series. They'll shoot up to 1000fps of video. The resolution isn't that hot but they are neat cameras.


Return to posts index

Randy Smith
Re: Slowing down Hummingbirds with Twixtor
on Mar 22, 2012 at 10:01:13 pm

Hi Brad,
Its interesting that we are trying to do the same thing with hummingbirds and Twixtor at the same time. I spent several hours trying to slow down hummingbird wings with Twixtor last night. I'm also shooting 1080p at 59.97fps with a Sony A77. I found that if I tried to set the frame rate too high (1000 or greater) it warped too much, but if I set frames to 240 or 360 per second and slowed it down to 50% it looked pretty good. Still not as smooth as 120fps real footage, but acceptable to me. Also I used Smart blend, and I used control/drag to stretch the clip. Let me know how its going for you, I don't think there a lot of us that have tried Twixtor with hummingbirds, but it is certainly a worthwhile challenge.

Randy


Return to posts index


Dave LaRonde
Re: Slowing down Hummingbirds with Twixtor
on Mar 23, 2012 at 3:12:37 pm

Um, sorry but the maximum frame rate on that camera is 60 (59.94?) frames/sec. You were adjusting some other parameter: ISO? Exposure time? Who knows? But it wasn't frame rate!

I recommend opening up the camera's manual and reading it.

Dave LaRonde
Sr. Promotion Producer
KCRG-TV (ABC) Cedar Rapids, IA


Return to posts index

Brad Weiss
Re: Slowing down Hummingbirds with Twixtor
on Mar 24, 2012 at 7:21:47 pm

Randy i'd be interested to see some of your test footage from your Sony A77 and see how it turned out. I have to admit i'm a little confused - as Dave mentioned - when you refer to "frame rate" did you by chance me "shutter speed"?

This would make more sense to me. Instead of double the shutter speed (120) when shooting at 60fps, you are tripling or quadrupling it.

I can post a test clip of what im experiencing...but the results were less than i was hoping for. Part of the learning process though!


clip to come.



Return to posts index

Randy Smith
Re: Slowing down Hummingbirds with Twixtor
on Mar 28, 2012 at 12:21:06 am

Hi Brad,
Perhaps my terminology was not correct, but when I was refrring to frame rate, I meant changing the number of frames in Twixtor. The A77 shoots at 59.94 fps I believe, and I was increasing the number of frames created by the Twixtor plug in. Honestly, I did a lot of trial and error to get the best results. I still have plenty to learn though. I'm rendering on a dual core processor, so even short clips are painfully slow. Here is a link to my hummingbird footage on vimeo:

The second of the three clips came out the best. Honestly, I'm beginning to think it was dumb luck. I was shooting AVCHD 1080p 60 at the highest bit rate possible 26. something kbps. I'm not sure about what my shutter speed was. I've been told I have ghosting because I'm shooting at too fast a shutter speed, and that I should shoot slower speeds to get some motion blur for Twixtor to work with, but I've read other posts that say that motion blur is bad and I should shoot as fast a shutter speed as possible to stop the motion. I say its some crazy mathematical formula that when it works right, it is magic. When it doesn't, it can be ugly. I really think it is the ratio of wing beats to shutter speed, to frame rate that has to be just right for it to work.


Return to posts index


Brad Weiss
Re: Slowing down Hummingbirds with Twixtor
on Mar 28, 2012 at 1:26:35 pm

Randy,

Thanks for sharing you clips. I can certainly see the ghosting effect in your first and third clip, which provides an interesting warping effect on the wings (if you desire that effect) but the ramping in the second clip (starting around 0:16) was most impressive as you were able to get full wing movement with little to no motion blur! Were there any changes in camera settings or post production tweaking between the first and second clip?

I have an observation that may account for the difference between clips 1&3 and clip 2, which is the body position of the hummingbird in relation to the camera

In clips 1&3 the birds are in profile to the camera, and thus showing the full "stroke" of the wing. In clip 2 the hummingbird seems to be almost head on with the camera, and therefore the action and speed of the wing movement is less exaggerated making it easier for Twixtor to interpret the frames inbetween.

I'm going to revisit my clips tonight and see if i can't find a similar shot to test this myself and will get back to you with my results.



Return to posts index

<< PREVIOUS   •   VIEW ALL   •   PRINT   •   NEXT >>
© 2017 CreativeCOW.net All Rights Reserved
[TOP]