View Full Version : remove frames in post


Elena Pastor
February 17th, 2010, 05:28 PM
Hi !
i´m going to make a videoclip in a few weeks. We are going to work with 7d and the redrock system :D (can´t wait!) i know we can shoot in 60f but i´m wondering if is possible to shoot in 24f and in post remove some frames so it will look quite slow motion. I would like that the image looks "suspendid" so people seems to be floating and dancing very very slow. Why not 60f you may wonder, i have the issue that the singer will be telling some parts of the song, and in 60f i guess i would loose the lipsing. What do you say?
thanks

Elena

Jon Fairhurst
February 17th, 2010, 05:53 PM
For slow motion, shoot at 60 and play back at 24. Yes, you will lose lip sync, but if you use a few well-placed clips that don't focus on the lips, it can be smooth and dreamy.

You don't want to shoot at 24 and drop frames. That would make it too fast. Like Charlie Chaplin.

Also, you probably want to shoot at a shutter of 1/50 for a smooth, natural look. If you shoot at 1/30, it will look mushy. If you shoot at 1/100 or higher, it will look stuttery, like a sequence of still, crisp, photos. This style is used in the Borne Identity fight scenes and storming the beach in Saving Private Ryan. Rather than a smooth dream, it becomes a frenzied dream. If you double frames (use half of the 24p frames, and show each frame twice), it will become even more intense.

Elena Pastor
February 17th, 2010, 06:06 PM
love chaplin but that not the way hahahaha my bad! :p
i actually want that it will look slowlly, more like a sleepy, chill thing.
So for what i get, the way is going with the 60f and playng at 24f, thats all great but i really need lipsing, he is a singer and after all this is a videoclip :D
about the shutter i have heard 7d doesn´t come with this video feature, unless is about the speed of shutter for photo, and there i´m lost
if i shoot at 24f and double the frames in post, will i loose lipsing?
sorry jon i´m quite lost!

David Chapman
February 17th, 2010, 07:25 PM
Elena, help me understand what you are trying to do. Do you want this to play in slow motion (slow moving people) but have the audio in real time with the lips?

You can slow down footage by shooting 60p and having that play in a 24p timeframe. This 60 frames per second then becomes 2.5 seconds at 24p because 60/24 = 2.5.

If I say the word "DAVE" at 60p and then convert so it plays in a 24p timeline, then my one second of "DAVE" is then spread out over 2.5 seconds and it sounds like "DAAAVVEEE".

Now...
If you want the action to be slow but the lips to be in real time, you will have to have your singer sing the song 2.5x faster so when slowed down it will look normal. You can do this by speeding up the recording song and then have them lip sync to "the chipmonks" and slow it down to match with the normal speed music.

Sample:
YouTube - Tutorial: HD100/200 How to shoot a Slow Motion Music Video with lip-sync (http://www.youtube.com/watch?v=icHyFaHg6-s)

Tim Dashwood! Haven't talked to him in forever. He rocks!

Alex Payne
February 17th, 2010, 07:51 PM
I'm also not sure if I understand what you're trying to do, but my take on it is that you want some parts to be slow motion and some parts to be regular motion.

Your answer may be to shoot at 24p and slow down the parts you want slow in post. I don't know about any other system but I know with final cut pro you can digitally slow things down at some sections and keep them at regular time (or speed them up) at others.

If however you want everything moving in slow motion EXCEPT the singer who is moving in regular motion, that sounds to me like a pretty nifty special effect which will require you to shoot everyone EXCEPT the singer at, say, 60fps (or, again, to slow it down in post) and shoot the singer on a green screen at 24fps and layer him over.

But I have no idea how to do that.

Bill Pryor
February 17th, 2010, 09:16 PM
Elena, if you're shooting at 24 fps, your shutter should be set at 1/50. If you're shooting at 60 fps, set the shutter at 1/120.

Craig Campbell
February 18th, 2010, 09:18 AM
Elena, help me understand what you are trying to do. Do you want this to play in slow motion (slow moving people) but have the audio in real time with the lips?

You can slow down footage by shooting 60p and having that play in a 24p timeframe. This 60 frames per second then becomes 2.5 seconds at 24p because 60/24 = 2.5.

If I say the word "DAVE" at 60p and then convert so it plays in a 24p timeline, then my one second of "DAVE" is then spread out over 2.5 seconds and it sounds like "DAAAVVEEE".

Now...
If you want the action to be slow but the lips to be in real time, you will have to have your singer sing the song 2.5x faster so when slowed down it will look normal. You can do this by speeding up the recording song and then have them lip sync to "the chipmonks" and slow it down to match with the normal speed music.

Sample:
YouTube - Tutorial: HD100/200 How to shoot a Slow Motion Music Video with lip-sync (http://www.youtube.com/watch?v=icHyFaHg6-s)

Tim Dashwood! Haven't talked to him in forever. He rocks!


Thanks for that tutorial its fantastic, just need to work out the numbers for shooting at 50 then 25, our students have a Music Video assignment and they always ask about these, have an answer now

Elena Pastor
February 21st, 2010, 07:24 PM
David, you are my heroe! :)
that tutorial is just what i needed!! thanks

Elena, if you're shooting at 24 fps, your shutter should be set at 1/50. If you're shooting at 60 fps, set the shutter at 1/120.

Bill: this speed shutter is to create any effect or just a rule for shooting video in drls?
Alex: that idea sound great if i have budget and knowllege in special effects :D