slow motion at DVinfo.net

Nagisa Kodama · August 9th, 2008, 01:17 PM

I usually shoot 30F and am thinking of using the footage to do slow motion in post.
I know that 60i would be better for that, and I have no problems with that, but I don't think final cut likes me mixing frame rates...

Bill Thesken · August 10th, 2008, 09:45 PM

Don't know about final cut, but I mix frame rates all the time in Vegas. Slow motion looks great in 60i, but terrible in 30f and 24f. I use the 24f for interviews, and 60i for action. Although I did a couple of interviews recently in 60i and could not really tell the difference. It was the pace of the interview, and the subject matter which caught the attention more than the frame rate.

Jonathan Shaw · August 10th, 2008, 10:26 PM

In final cut you can use the media manager to match / alter frame rate etc. I generally shoot 50i but have mixed in 25F no problems.

Paul Whittington · August 11th, 2008, 12:08 AM

Hey Nagisa, if you're using Final Cut 6 and have Final Cut Studio 2 and want the best slow motion possible then use Motion - it will give you the best results no matter which frame rate you're using.

David McGiffert · August 11th, 2008, 12:37 AM

Paul,

I totally agree.
If you want great slow motion use Motion.
The results are beautiful.

David

Bill Thesken · August 15th, 2008, 03:21 PM

Can anyone provide an example of 30F slow motion?
My experiments look chuttery. Only 60i w180-210 shutter looks silky smooth for slowmo.

Paul Whittington · August 15th, 2008, 06:55 PM

Hey Bill... You know, I never use either of the F-modes with the A1 - with my A1, even at normal speed, those modes looked very choppy so I'm not surprised when you say they look that way in slow-motion as well. I guess it's best to stick with 60i if you can.

Adrian Stucker · August 21st, 2008, 03:27 PM

The best slow motion I've achieved is shooting 60i, shutter <100. Capture, then bring into after effects. Right click the footage in the project manager, and select "interpret footage" Using "upper fields first" option, and conform to 23.98 fps.

This effectively separates the field into 60fps. Then using the "Time Stretch" you can stretch up to 250%. Make sure motion blur is off. results are breath taking.

Jo Potts · August 21st, 2008, 03:56 PM

If you want brilliant slow motion and are using FCS2 then chuck it into motion and set the retiming option to optical flow - it will take a little while to analyse your clip (which only needs doing once, no matter how many times you change the speed afterwards) and produces some stunning results - no matter what frame rate or shutter speed (i've used it on some pretty poor footage and made it look fairly decent!).

Obviously if you don't have Final Cut, then ignore this!

It's worth noting that if you only want it on a small section, then make sure you don't send a whole clip to motion. I'm not sure whether it analyses the whole file (as it sits on the disk) or whether just the in and out points you've sent it - but either way, you don't want to waste your time...although it does work in the background so you can carry on with other stuff.

Mike Flynn · August 21st, 2008, 06:12 PM

I have been struggling with slow motion for the past couple years now. I love the look of 30f, but I generally shoot high action sports (motocross, etc) and just slowing the footage down using Final Cut produces a stuttery image most of the time.

This year I switched to 60i for shooting motocross, but I absolutely hate the look of 60i on a television. Good thing most of my work is for the web.

I recently shot a wedding using 24f. I was a little worried about how the slow motion would turn out, but I think it is going to be wonderful. Just 10 minutes ago I ran this test on a piece of footage: http://magic-mike.net/temp/weddingslowmo.mov

My workflow was: Twixtor Pro plug in, slowed down to 28%. Then added some SmoothCam (never even used SmoothCam before so I don't know what I'm doing). I am pretty happy with that result, especially since it started at 24f. Obviously there is very little movement in the shot, which helps to create a smooth image. With high moving images, Twixtor will leave you with warped areas that aren't useable. I would recommend trying Twixtor if you think your footage isn't too high action.

EDIT: Also wanted to add that I agree with the others that have said it, Motion produces far better slow motion than Final Cut Pro. Even just using a Motion Blend as opposed to Optical Flow with leave you with much better results.

Adrian Stucker · August 25th, 2008, 10:05 PM

Remember if you shoot 60i you can make beautiful slow motion, then render you entire project to 24p, you can always go down, but never up.

Here is an example using the XH-A1 with 60i slow motion. I used a shutter of 1/60 and it produces a blur, for this project I like it.

But generally if you shoot above 1/100, it will be very crisp.

Mike Skates Downtown on Vimeo

Pavel Tomanec · August 26th, 2008, 04:45 AM

Quote:

Originally Posted by Adrian Stucker

Remember if you shoot 60i you can make beautiful slow motion, then render you entire project to 24p, you can always go down, but never up.

Thanks for sharing your video. It's quite OK.

I wonder though about the issues regarding vertical resolution. I keep hearing that Canon's frame mode is 15-20% less than full resolution (1080 pixels) but the 50/60i is 1080i lines interlaced so theoretically after de-interlacing you end up only with 540 lines!

For film transfer or Blue Ray this would be definitely insufficient. Would people kindly shed some light on this issue again?

I am especially interested exploring the possibilities/limitations in relation to slow motion/fast motion. I am happy to hear about the quality of slow motion in Motion. I must admit that I was not very happy with the slow motion produced by Final Cut Pro 6. Thanks for sharing the knowledge, much appreciated.

Many thanks,
Regards,
Pavel

Jonathan Levin · August 26th, 2008, 07:31 PM

Greetings.

Back in the day when I was shooting film, going to anything above 24fps, like 30, 60, 100fps and so on is what would give you the effect of slow motion, although you had to adjust the aperature to a larger f/stop. The film passing through the gate of a projector is still going at 24fps, so the higher "shutter speed" on the camera is what produced the slo-mo.

On video, isn't it the same? Video is "traveling"at (roughly) 30fps, it's being "projected" (tv, monitor, etc) at 30fps, so it seems that just changing the shutter speed (and adjusting the aperature accordingly) of the video camera to say 60, or 80 fps would just automatically give you the desired slo-mo effect. No? I still get confused by the differences or simularities of "60i" which translates to 30fps. I understand that because of interlace, each frame is actually two frames, if you will.

But this is a seperate entity from the actual shutter speed of the camera, right?

Thanks for all this info.

Jonathan

I think this was explained

Bill Pryor · August 26th, 2008, 07:46 PM

Correct. Shutter speed has little to do with slow motion. Faster frame rate gives you real slow motion, just like in film. However, if you don't have a camera with variable frame rates, you can approximate a slow motion look with software. It's never going to be as good, but you can slow a shot down up to a point without it looking too jerky.

Adrian Stucker · August 26th, 2008, 07:52 PM

In your first paragraph I think you are confusing shutter speed with frames per second. The shutter is how often the camera lets light in.

The frames per second are not affected by the shutter.
For example if you are shooting 24fps, and the shutter is 1/250, the frame is exposed every 1/250 of a second, but not more frames are being created.

does this help?

August 9th, 2008, 01:17 PM	#1
Nagisa Kodama Regular Crew Join Date: Jul 2007 Location: California Posts: 28	slow motion I usually shoot 30F and am thinking of using the footage to do slow motion in post. I know that 60i would be better for that, and I have no problems with that, but I don't think final cut likes me mixing frame rates...

August 10th, 2008, 10:26 PM	#3
Jonathan Shaw Major Player Join Date: Nov 2007 Location: Sydney Posts: 552	In final cut you can use the media manager to match / alter frame rate etc. I generally shoot 50i but have mixed in 25F no problems. __________________ www.ginclearfilm.com www.facebook.com/ginclearfilm

August 21st, 2008, 03:27 PM	#8
Adrian Stucker New Boot Join Date: Aug 2008 Location: Cincinnati, Ohio Posts: 13	slowmo The best slow motion I've achieved is shooting 60i, shutter <100. Capture, then bring into after effects. Right click the footage in the project manager, and select "interpret footage" Using "upper fields first" option, and conform to 23.98 fps. This effectively separates the field into 60fps. Then using the "Time Stretch" you can stretch up to 250%. Make sure motion blur is off. results are breath taking.

August 21st, 2008, 03:56 PM	#9
Jo Potts Regular Crew Join Date: Apr 2008 Location: Cambridge, UK Posts: 40	If you want brilliant slow motion and are using FCS2 then chuck it into motion and set the retiming option to optical flow - it will take a little while to analyse your clip (which only needs doing once, no matter how many times you change the speed afterwards) and produces some stunning results - no matter what frame rate or shutter speed (i've used it on some pretty poor footage and made it look fairly decent!). Obviously if you don't have Final Cut, then ignore this! It's worth noting that if you only want it on a small section, then make sure you don't send a whole clip to motion. I'm not sure whether it analyses the whole file (as it sits on the disk) or whether just the in and out points you've sent it - but either way, you don't want to waste your time...although it does work in the background so you can carry on with other stuff. __________________ MBP 15" 2.6Ghz, 4GB RAM. 2TB storage. FCS2. Canon XH-A1. www.jpcreativemedia.com vimeo.com/user449069

August 25th, 2008, 10:05 PM	#11
Adrian Stucker New Boot Join Date: Aug 2008 Location: Cincinnati, Ohio Posts: 13	slow motion Remember if you shoot 60i you can make beautiful slow motion, then render you entire project to 24p, you can always go down, but never up. Here is an example using the XH-A1 with 60i slow motion. I used a shutter of 1/60 and it produces a blur, for this project I like it. But generally if you shoot above 1/100, it will be very crisp. Mike Skates Downtown on Vimeo

August 10th, 2008, 09:45 PM	#2
Bill Thesken Major Player Join Date: May 2008 Location: HI, USA Posts: 622	Don't know about final cut, but I mix frame rates all the time in Vegas. Slow motion looks great in 60i, but terrible in 30f and 24f. I use the 24f for interviews, and 60i for action. Although I did a couple of interviews recently in 60i and could not really tell the difference. It was the pace of the interview, and the subject matter which caught the attention more than the frame rate.

August 11th, 2008, 12:08 AM	#4
Paul Whittington Regular Crew Join Date: Jul 2008 Location: Vancouver Island Posts: 106	Hey Nagisa, if you're using Final Cut 6 and have Final Cut Studio 2 and want the best slow motion possible then use Motion - it will give you the best results no matter which frame rate you're using.

August 11th, 2008, 12:37 AM	#5
David McGiffert Regular Crew Join Date: Feb 2007 Location: Topanga, CA Posts: 139	Paul, I totally agree. If you want great slow motion use Motion. The results are beautiful. David

August 15th, 2008, 03:21 PM	#6
Bill Thesken Major Player Join Date: May 2008 Location: HI, USA Posts: 622	Can anyone provide an example of 30F slow motion? My experiments look chuttery. Only 60i w180-210 shutter looks silky smooth for slowmo.

August 15th, 2008, 06:55 PM	#7
Paul Whittington Regular Crew Join Date: Jul 2008 Location: Vancouver Island Posts: 106	Hey Bill... You know, I never use either of the F-modes with the A1 - with my A1, even at normal speed, those modes looked very choppy so I'm not surprised when you say they look that way in slow-motion as well. I guess it's best to stick with 60i if you can.

August 21st, 2008, 06:12 PM	#10
Mike Flynn Regular Crew Join Date: Sep 2004 Location: Renton, WA Posts: 94	I have been struggling with slow motion for the past couple years now. I love the look of 30f, but I generally shoot high action sports (motocross, etc) and just slowing the footage down using Final Cut produces a stuttery image most of the time. This year I switched to 60i for shooting motocross, but I absolutely hate the look of 60i on a television. Good thing most of my work is for the web. I recently shot a wedding using 24f. I was a little worried about how the slow motion would turn out, but I think it is going to be wonderful. Just 10 minutes ago I ran this test on a piece of footage: http://magic-mike.net/temp/weddingslowmo.mov My workflow was: Twixtor Pro plug in, slowed down to 28%. Then added some SmoothCam (never even used SmoothCam before so I don't know what I'm doing). I am pretty happy with that result, especially since it started at 24f. Obviously there is very little movement in the shot, which helps to create a smooth image. With high moving images, Twixtor will leave you with warped areas that aren't useable. I would recommend trying Twixtor if you think your footage isn't too high action. EDIT: Also wanted to add that I agree with the others that have said it, Motion produces far better slow motion than Final Cut Pro. Even just using a Motion Blend as opposed to Optical Flow with leave you with much better results.

August 26th, 2008, 07:31 PM	#13
Jonathan Levin Major Player Join Date: Apr 2008 Location: Chicago, Illinois USA Posts: 692	Greetings. Back in the day when I was shooting film, going to anything above 24fps, like 30, 60, 100fps and so on is what would give you the effect of slow motion, although you had to adjust the aperature to a larger f/stop. The film passing through the gate of a projector is still going at 24fps, so the higher "shutter speed" on the camera is what produced the slo-mo. On video, isn't it the same? Video is "traveling"at (roughly) 30fps, it's being "projected" (tv, monitor, etc) at 30fps, so it seems that just changing the shutter speed (and adjusting the aperature accordingly) of the video camera to say 60, or 80 fps would just automatically give you the desired slo-mo effect. No? I still get confused by the differences or simularities of "60i" which translates to 30fps. I understand that because of interlace, each frame is actually two frames, if you will. But this is a seperate entity from the actual shutter speed of the camera, right? Thanks for all this info. Jonathan I think this was explained

August 26th, 2008, 07:46 PM	#14
Bill Pryor Contributor Join Date: Jan 2003 Location: Kansas City, MO Posts: 4,449	Correct. Shutter speed has little to do with slow motion. Faster frame rate gives you real slow motion, just like in film. However, if you don't have a camera with variable frame rates, you can approximate a slow motion look with software. It's never going to be as good, but you can slow a shot down up to a point without it looking too jerky.

August 26th, 2008, 07:52 PM	#15
Adrian Stucker New Boot Join Date: Aug 2008 Location: Cincinnati, Ohio Posts: 13	In your first paragraph I think you are confusing shutter speed with frames per second. The shutter is how often the camera lets light in. The frames per second are not affected by the shutter. For example if you are shooting 24fps, and the shutter is 1/250, the frame is exposed every 1/250 of a second, but not more frames are being created. does this help?