Jittery Slow Mo in CS5 at DVinfo.net

Kristian Roque · October 22nd, 2010, 07:51 PM

So I am trying to really smooth out this clip that I decreased the speed to 50%. But man, I get this annoying jittery outcome. The footage I am using is 1920x1080p at 24fps. I have already looked online on other sites. The recommendations I get are to select the 'Frame Blend", but does not seem to work at all. Anyone have any other recommendations? Thank you so much.

Adam Gold · October 22nd, 2010, 11:34 PM

Unfortunately, 24fps if the worst possible frame rate if you want to do slow mo. Frame blend is the best you can do with Premiere without going to outside third party add-ins, and even those may not give you what you want. There just aren't enough pictures per second to give you nice smooth slomo if you shoot 24p.

All that being said, you may have better luck in AE rather than Premiere.

Robert Young · October 23rd, 2010, 12:31 AM

That's really a challenge.
At 50% slo mo, you have only 12 fps of real data to work with. That is going to be jittery.
At that frame rate, the various blending options will probably soften the image more than smooth it out.
You may have to compromise to 75%, etc. to get an acceptable look.

Richard Lucas · October 24th, 2010, 07:33 PM

If you have access to After Effects and the clip you want to make slo-mo isn't too long, there is a way to do it in AE and make it look smooth. Can't recall the name exactly but it was something like "Time Remapping". There are two ways to do it. The cheap and cheerful way is via frame blending, which seems very much identical to how Premier does it. The other one, which I think is called interpolation where it basically makes "tween" frames by computing the different existing frames. It is amazingly slow and cpu intensive. It can work well, but sometimes it looses the recipe and you end up with weird artifacts. You can tune the parameters a bit, which can help some but to get it all right you REALLY have to want to commit the time to make it work right.

I've used it on a couple of 10-15 second clips and did get it to look good.

It's an option.

Zoran Vincic · October 25th, 2010, 03:53 AM

24p ain't that much worse than 25p that I regulary work with.

Premiere's own slowmotion isn't very good with progressive footage even with frame blending (it's ok when using 50/60i material).

If you have AE you could send the clip there via dynamic link and use timewarp plugin.

Or you could do what I did, just buy the premiere plugin called Twixtor. It has the most painless workflow and yields a great result.

Bart Walczak · October 26th, 2010, 11:10 AM

CS5 has frame blending turned off by default (finally). You can try switching it on (right click on the clip, select frame blending), and see if the effect is more satisfying. It probably won't, but you never know.

John Knight · January 7th, 2011, 11:52 PM

I've having the same problem with Premiere CS5 and 1080/50i footage.

Using 50% slowmo in CS3 was silky smooth, but I get a jittery effect in CS5 with the same footage. Checking the frame blend option seems to have no difference. Help!

Chris Duczynski · January 8th, 2011, 06:21 PM

You could also try shooting manually at a faster shutter speed if you intend to slo-mo it. Works much better in post.

Brian Tori · January 10th, 2011, 06:46 PM

I've had good luck with this method.

1. In the project window, select the clip you want to slow down.
2. Right click select modify.
3. Select interpret footage.
4. Select the option to assume framerate and choose 12fps to start.

12fps would be half the framerate of 24p, this equals a 50% slowdown.

Kevin Monahan · January 10th, 2011, 08:32 PM

Here's what I've got. Don't forget to check out the linked tutorials: Adobe After Effects CS5 * Time-stretching and time-remapping

October 22nd, 2010, 07:51 PM	#1
Kristian Roque Regular Crew Join Date: May 2010 Location: Spring Valley CA Posts: 55	Jittery Slow Mo in CS5 So I am trying to really smooth out this clip that I decreased the speed to 50%. But man, I get this annoying jittery outcome. The footage I am using is 1920x1080p at 24fps. I have already looked online on other sites. The recommendations I get are to select the 'Frame Blend", but does not seem to work at all. Anyone have any other recommendations? Thank you so much.

October 22nd, 2010, 11:34 PM	#2
Adam Gold Inner Circle Join Date: Jan 2007 Location: Woodinville, WA USA Posts: 3,467	Unfortunately, 24fps if the worst possible frame rate if you want to do slow mo. Frame blend is the best you can do with Premiere without going to outside third party add-ins, and even those may not give you what you want. There just aren't enough pictures per second to give you nice smooth slomo if you shoot 24p. All that being said, you may have better luck in AE rather than Premiere. __________________ "It can only be attributable to human error... This sort of thing has cropped up before, and it has always been due to human error."

October 23rd, 2010, 12:31 AM	#3
Robert Young Trustee Join Date: Mar 2005 Location: Coronado Island Posts: 1,472	That's really a challenge. At 50% slo mo, you have only 12 fps of real data to work with. That is going to be jittery. At that frame rate, the various blending options will probably soften the image more than smooth it out. You may have to compromise to 75%, etc. to get an acceptable look. __________________ Bob

January 7th, 2011, 11:52 PM	#7
John Knight Major Player Join Date: May 2008 Location: Auckland, New Zealand Posts: 588	I've having the same problem with Premiere CS5 and 1080/50i footage. Using 50% slowmo in CS3 was silky smooth, but I get a jittery effect in CS5 with the same footage. Checking the frame blend option seems to have no difference. Help! __________________ Over 28 years watching TV

January 10th, 2011, 08:32 PM	#10
Kevin Monahan Adobe Systems Join Date: Dec 2010 Location: San Francisco, CA Posts: 191	Here's what I've got. Don't forget to check out the linked tutorials: Adobe After Effects CS5 * Time-stretching and time-remapping __________________ Kevin Monahan - Support Product Manager—DVA After Effects - Premiere Pro - Media Encoder - Prelude - SpeedGrade - Encore

October 24th, 2010, 07:33 PM	#4
Richard Lucas Regular Crew Join Date: Sep 2010 Location: Sarasota, FL Posts: 55	If you have access to After Effects and the clip you want to make slo-mo isn't too long, there is a way to do it in AE and make it look smooth. Can't recall the name exactly but it was something like "Time Remapping". There are two ways to do it. The cheap and cheerful way is via frame blending, which seems very much identical to how Premier does it. The other one, which I think is called interpolation where it basically makes "tween" frames by computing the different existing frames. It is amazingly slow and cpu intensive. It can work well, but sometimes it looses the recipe and you end up with weird artifacts. You can tune the parameters a bit, which can help some but to get it all right you REALLY have to want to commit the time to make it work right. I've used it on a couple of 10-15 second clips and did get it to look good. It's an option.

October 25th, 2010, 03:53 AM	#5
Zoran Vincic Regular Crew Join Date: Jul 2010 Location: Split, Croatia Posts: 189	24p ain't that much worse than 25p that I regulary work with. Premiere's own slowmotion isn't very good with progressive footage even with frame blending (it's ok when using 50/60i material). If you have AE you could send the clip there via dynamic link and use timewarp plugin. Or you could do what I did, just buy the premiere plugin called Twixtor. It has the most painless workflow and yields a great result.

October 26th, 2010, 11:10 AM	#6
Bart Walczak Major Player Join Date: Apr 2006 Location: Warsaw/Poland Posts: 716	CS5 has frame blending turned off by default (finally). You can try switching it on (right click on the clip, select frame blending), and see if the effect is more satisfying. It probably won't, but you never know.

January 8th, 2011, 06:21 PM	#8
Chris Duczynski Major Player Join Date: Feb 2010 Location: sydney Posts: 304	You could also try shooting manually at a faster shutter speed if you intend to slo-mo it. Works much better in post.

January 10th, 2011, 06:46 PM	#9
Brian Tori Major Player Join Date: Nov 2004 Location: Detroit, MI Posts: 408	I've had good luck with this method. 1. In the project window, select the clip you want to slow down. 2. Right click select modify. 3. Select interpret footage. 4. Select the option to assume framerate and choose 12fps to start. 12fps would be half the framerate of 24p, this equals a 50% slowdown.