Slow-motion jitter at DVinfo.net

Dan Robinson · October 30th, 2006, 07:38 PM

When I slow down a clip in Premiere, there is a pronounced vertical jitter in the resulting exported footage. Apparently this is called 'field bob', caused by the slight vertical shift between interlaced frame halves. I did some searching and tweaking of settings but wasn't able to find a fix. Has anyone found a solution to 'field bob' in Premiere?

Here is a sample of what happens (clip is 2.4MB full-screen WMV):

http://wvlightning.com/stuff/slomojitter.wmv

Thanks in advance for any advice!

Dan Robinson · October 30th, 2006, 11:52 PM

Another bit of info - unchecking 'Frame Blend Speed Changes' and choosing 'flicker removal' in the Field Options window removes the 'field bob' but also removes the smoothing between frames, creating a more 'stepped' appearance rather than a smooth slow-motion image.

Dan Robinson · November 1st, 2006, 01:12 PM

One last bump to see if anyone has had this problem.

Adam Bray · November 1st, 2006, 07:57 PM

Slow motion with video is never that great. Best option that I know of is to just shoot in 60i and pray. Maybe try some software like Shake. But I have no experience with it.

Dale Guthormsen · November 8th, 2006, 03:07 PM

The best program out there for slo mo is twixtor, but it is a few hundered bucks.

I am not sure shooting in interelaced is the best to make slow mo. I use 30 p and it is reasonable.

Joshua Clarke · November 10th, 2006, 09:59 AM

Adam is right in that slow-mo on video is never good. However, I found a decent alternative if you can't frame ramp with video. Shoot in 60i with a shutter speed of 1/120 to get the crispest image. Use field interpolate on the 60i image in your timeline and save as a 24p or 30p, whatever you're using, lossless file. Import that file into your finished product and it should work. Don't take this as scripture. I've only done it once and I've probably forgotten a few steps, but try it out and let me know.

Cal Johnson · November 10th, 2006, 11:29 AM

Dale is right, Twixtor is awesome.

Calvin Wallace · November 14th, 2006, 03:21 AM

Do you mean that it looks like the camera is shaking up and down, like it's not on a steady tripod?

Dave Ferdinand · November 14th, 2006, 07:32 AM

You could use my filter for VirtualDub to turn the footage from 60i to 60p and then use that in a 24p/30p timeline in PPro. It will give you super smooth slowmo.

It's not the same as doing it inside Premiere bu they're both free, fast and very easy to use.

http://www.geocities.com/headlesspup...f/vdub_60p.zip
http://www.virtualdub.org/

Good luck.

Ben Winter · November 15th, 2006, 02:17 AM

Also, "motionperfect" from dynapel interpolates frames to give extra-smooth slow-mo. I use my music video "one headlight" at http://qt.frozenphoenixproductions.com as a great example of what it can do.

October 30th, 2006, 07:38 PM	#1
Dan Robinson Regular Crew Join Date: Mar 2004 Location: Charleston, West Virginia Posts: 131	'Field Bob' problem - eliminating slow-motion jitter? When I slow down a clip in Premiere, there is a pronounced vertical jitter in the resulting exported footage. Apparently this is called 'field bob', caused by the slight vertical shift between interlaced frame halves. I did some searching and tweaking of settings but wasn't able to find a fix. Has anyone found a solution to 'field bob' in Premiere? Here is a sample of what happens (clip is 2.4MB full-screen WMV): http://wvlightning.com/stuff/slomojitter.wmv Thanks in advance for any advice! Last edited by Dan Robinson; October 30th, 2006 at 11:44 PM.

November 8th, 2006, 03:07 PM	#5
Dale Guthormsen Inner Circle Join Date: Jun 2005 Location: Saskatchewan Posts: 3,048	slo mo The best program out there for slo mo is twixtor, but it is a few hundered bucks. I am not sure shooting in interelaced is the best to make slow mo. I use 30 p and it is reasonable. __________________ DATS ALL FOLKS Dale W. Guthormsen

November 10th, 2006, 09:59 AM	#6
Joshua Clarke Regular Crew Join Date: Jul 2006 Location: Philadelphia, PA Posts: 88	Adam is right in that slow-mo on video is never good. However, I found a decent alternative if you can't frame ramp with video. Shoot in 60i with a shutter speed of 1/120 to get the crispest image. Use field interpolate on the 60i image in your timeline and save as a 24p or 30p, whatever you're using, lossless file. Import that file into your finished product and it should work. Don't take this as scripture. I've only done it once and I've probably forgotten a few steps, but try it out and let me know. __________________ Section 1 Films Last edited by Joshua Clarke; November 10th, 2006 at 01:46 PM.

November 14th, 2006, 03:21 AM	#8
Calvin Wallace New Boot Join Date: Apr 2006 Location: Edmonton, AB, CAN Posts: 20	Do you mean that it looks like the camera is shaking up and down, like it's not on a steady tripod? __________________ http://www.darkbyke.deviantdesign.ca Canon Elura 65 Adobe Premiere 1.5 Pro Song VAIO PC / 3GHz / 1.5GB ram / 710GB capacity

November 14th, 2006, 07:32 AM	#9
Dave Ferdinand Major Player Join Date: Jan 2005 Location: Vancouver, BC Posts: 359	You could use my filter for VirtualDub to turn the footage from 60i to 60p and then use that in a 24p/30p timeline in PPro. It will give you super smooth slowmo. It's not the same as doing it inside Premiere bu they're both free, fast and very easy to use. http://www.geocities.com/headlesspup...f/vdub_60p.zip http://www.virtualdub.org/ Good luck. __________________ Do or do not, there is no try.

October 30th, 2006, 11:52 PM	#2
Dan Robinson Regular Crew Join Date: Mar 2004 Location: Charleston, West Virginia Posts: 131	Another bit of info - unchecking 'Frame Blend Speed Changes' and choosing 'flicker removal' in the Field Options window removes the 'field bob' but also removes the smoothing between frames, creating a more 'stepped' appearance rather than a smooth slow-motion image.

November 1st, 2006, 01:12 PM	#3
Dan Robinson Regular Crew Join Date: Mar 2004 Location: Charleston, West Virginia Posts: 131	One last bump to see if anyone has had this problem.

November 1st, 2006, 07:57 PM	#4
Adam Bray Major Player Join Date: Sep 2004 Location: Houston/Austin Posts: 394	Slow motion with video is never that great. Best option that I know of is to just shoot in 60i and pray. Maybe try some software like Shake. But I have no experience with it.

November 10th, 2006, 11:29 AM	#7
Cal Johnson Major Player Join Date: Oct 2004 Posts: 180	Dale is right, Twixtor is awesome.

November 15th, 2006, 02:17 AM	#10
Ben Winter Trustee Join Date: Jun 2005 Location: Hollywood, CA Posts: 1,675 Images: 1	Also, "motionperfect" from dynapel interpolates frames to give extra-smooth slow-mo. I use my music video "one headlight" at http://qt.frozenphoenixproductions.com as a great example of what it can do. __________________ BenWinter.com