View Full Version : Jittery Footage


Chris Cherrett
July 1st, 2007, 03:13 PM
I noticed some fast pans taken with my hd100 are jittery. They seem to jump a bit. I was shooting at 24p and no auto smoothing. Would it help to run at 30p with auto smoothing?

Adam Grunseth
July 1st, 2007, 04:45 PM
To answer your question, in short, yes, a faster frame rate with smoothing would help. Shooting at 24p, as I'm sure you know, is shooting the same frame rate as film- thus all the same rules you would follow with film in regards to panning and zoom speed you need to follow with 24p.

24p was first selected to be used in film as a comprimize.... it was fast enough to provide OK motion rendering, but yet not so fast as to be waistful. Over time this low temporal resolution became associated with film, which is why modern digital cinema cameras shoot at 24p in order to attempt to mimic the film look. However, shooting subjects with lots of motion can suffer at such a low frame rate, and, as you noticed, fast pans will not always look the best.

Chris Cherrett
July 1st, 2007, 05:03 PM
Thanks for the reply Adam. I did not know that there were specific guidelines to shooting 24p but now that you mention it, it would make good logic that it would have it's own quirks. I am just learning most of my video skills and am having great fun doing so. With learning comes it's bumps and I am for sure taking bumps :)

So would 30p + smoothing create noticeably smoother results that 24p + smoothing?

Thanks Again!

Off to learn how to rack focus with my stock hard to rack focus lens :)

Adam Grunseth
July 1st, 2007, 05:19 PM
Smoothing in general will greatly help improve your pans, however I try to avoid smoothing as it accomplishes the smooth effect by bluring the motion. However you end up with less stutter.

As far as if there is a noticable difference between 30p and 24p, that depends on how fast your panning. Yes, you will be able to pan faster with 30p than 24p, but once you excede either frame rates "maximum pan speed" you will get jitter. The maximum pan speed with 30p is just greater than it is with 24p.

Tom Chaney
July 16th, 2007, 04:50 AM
Hi Guys,

I've found that if you pan with something, a football player, a bird, a passing car, that it helps hide the jutter.

We shoot a lot of sports and have never had a complaint.

Good luck,

Tom

David Scattergood
July 16th, 2007, 06:07 AM
^^ Definitely. Tracking a moving object/person works really well. Apparantly this is why you only see cars in car chases from certain angles in 'hollywood' (behind and in front and tracked).

For really smooth and slow pans I use a sophisticated...elastic band to draw/pull the tripod arm (having a fluid tripod helps also).

Jon Enkel
July 16th, 2007, 08:36 AM
For really smooth and slow pans I use a sophisticated...elastic band to draw/pull the tripod arm (having a fluid tripod helps also).[/QUOTE]

What a fantastic tip David, love it!

David Scattergood
July 16th, 2007, 11:37 AM
For really smooth and slow pans I use a sophisticated...elastic band to draw/pull the tripod arm (having a fluid tripod helps also).

What a fantastic tip David, love it![/QUOTE]

Passed onto me by someone who I believe resides in the Cambridge area as it happens (and sometime DVinfo member - cheers Nige!)...and in turn that was passed on by a veteran in the BBC. Works really well (a nice soft stop as you release the pull on the elastic). Get it right and looks almost motor/computer controlled :)

Scott Jaco
July 17th, 2007, 04:13 PM
I noticed some fast pans taken with my hd100 are jittery. They seem to jump a bit. I was shooting at 24p and no auto smoothing. Would it help to run at 30p with auto smoothing?

I shoot events with 30p & motion smoothing turned on.

I've shot without motion smoothing and the strobe effect is more noticable.

The motion smoothing creates an image smear effect to make it a bit easier on the eyes during playback. I don't know why it gets such a bad rap.

If you plan to take a lot of video stills from your footage, it may be best to turn it off to avoid a ghosting/tracer effect on the stills, because that's how motion smoothing works. It creates a double exposure on each frame. Remember, your HD100 is actually a 720/60p camera.