• Wondering which camera, gear, computer, or software to buy? Ask in our Gear Guide.

Why does 24fps look choppy?

H

harmonica44

It doesn't show up on youtube or a smaller screen but 24 fps does look choppy when blown up. Basically the room vibrates when I pan and tilt the camera. It only happens on 24p though. Is this okay, or do is this a DSLR thing that I need to do something in post to look more professional?
 
Last edited:
Sort by date Sort by votes
Dude, you ask way too many questions without posting an example of what you're talking about. I'd try to answer your question, but I have no F-ing clue what you mean when you say that "the room vibrates", when you pan or tilt. Just post a clip.

No, 24 fps is not choppy. Maybe your shutter speed is too fast. Or maybe you've got some kind of jello-like effect. From the way you describe, I can't say.
 
Upvote 0 Downvote
Are you trying to describe rolling shutter which is something that most cmos cameras are prone to?

Or are you trying to describe a lack of tripod when you're panning and tilting?

Or something else?

That footage just looked like you were panning a little fast.
 
Upvote 0 Downvote
The ASC manual has a chart of max recommended pan speeds per shutter speed etc.

These thing should always be taken into account - you have to understand the rules before you can break them - you have to know why you're breaking them

Often I see people complain about choppy pans, or whip pans that make them feel sick - that's the exact reason the ASC manual exists; you know that you're safe if you pan at no faster than x speed.
 
Last edited:
Upvote 0 Downvote
Okay thanks. I tried playing it back on 3 monitors now to ask for friends opinions, so it's definitely not my monitor. I think it sounds like what Jax rox said. A DP I am working with says the trick to shoot at 60i, and then convert to 24p but I think that will just complicate the shoots I want to do one set, lighting and exposure wise.

But a lot of pro movies do fast pans while shooting at 24p. Like even Sam Raimi has done movies like that for example. So is it acceptable on my camera, the T2i then? What if I want to do a fast one for effect?
 
Last edited:
Upvote 0 Downvote
First of all this looks like handheld shot so it's normal not to be that good especially if you haven't put much time into it.

Secondly if you invest into a descent tripod you might be able to do some nice smooth tilts and pans.

However you must be aware of the rolling shutter issue on those DSLR as well.Shoot in lower shutter speed for motion blur such as 1/50 and not something like 100 or 200 .

And maybe try to stabilize it in post.
 
Upvote 0 Downvote
harmonica44 said:
A DP I am working with says the trick to shoot at 60i, and then convert to 24p but I think that will just complicate the shoots I want to do one set, lighting and exposure wise.
Click to expand...

That's a terrible suggestion, and I'd be immediately suspicious of anyone calling themselves a 'DP' who suggested something like that. The problem is either using too high a shutter speed, or panning too fast - jax's recommendation is spot on, you have to learn what the safe limits are for panning speed at any given shutter speed.
 
Upvote 0 Downvote
Okay. Two people I am collaborating with on shooting movies noticed a chopiness as the pointed out. I only noticed it a lot with the pillars in the parking lot, as the pillars vibrate during the pan on a bigger screen. But if this is normal for 24 at 1/50 then that's okay I guess. What if I want to pan fast though for effect? I want to do a shootout in the parking garage, and want some of the shots to be fast pans and tilts. Other shots I want to do fast tracking steadicam shots, as the actors run.
 
Upvote 0 Downvote
You can get away with faster pans or tracking shots as long as the subject in the frame is relatively stable in the shot - i.e. a person running stays in roughly the same screen area as the camera pans with them - because the viewer will focus on them and be less aware of the judder in the background. It's really only distracting to the viewer when everything in the frame is moving at once like your sample shot. For quick pans in a fast cut/moving sequence it's not going to be too noticeable either, it's worst when you force the audience to watch a single fast panning shot for too long.

But again - this is normal. It's present in pretty much every feature film to hit theaters. It's more noticeable on the big screen than on a television, but if you're careful to shoot around it (based on the guidelines in the ASC reference jax mentioned) people just won't notice.

If you play the same clip over and over for your friends asking if they notice it then yes, everyone's going to notice it - in fact, they probably won't be able to un-see it, and you've now ruined that shot for them. Which brings us to another important rule - if there's something about a shot or your film which bothers you, never ever ever point it out to the audience. Chances are they won't even notice it, but once you've told them to look for it they probably can't miss it.
 
Upvote 0 Downvote
Alright here's the difference between Sam Raimi's fast pans on film and your fast pans on DSLR:
He's using FILM. The light exposes the entire piece of film coated with chemicals and all the chemicals do their thing at the EXACT same time.
You're using a computer. The light exposes the entire CMOS sensor at the same time but the computer has to read it line by line = time. By the time the computer reads from the top to the bottom the next frame's top is waaaaaaay over somewhere else.
Thus the jello effect.

mesmerizing_5b312f_2768966.gif
 
Upvote 0 Downvote
Okay thanks. I actually didn't take notice of this until they pointed it out.

I know Raimi is using film but how are we suppose to make goodlooking stylistic movies, if we can't even do what the pros do in their camera movements?
 
Upvote 0 Downvote
rayw said:
He's using FILM. The light exposes the entire piece of film coated with chemicals and all the chemicals do their thing at the EXACT same time.
Click to expand...

Actually, that's technically not correct. The mechanical shutter in a film camera sweeps across the film plane, so there is the possibility of rolling shutter effects - it just does so faster than the readout of most CMOS sensors so the effect is greatly minimized. As digital readout speeds get faster with each new generation of cameras it should become less and less noticeable.

But that's beside the point - what he's pointing out in the panning clip is just standard 24fps judder. You get it with film cameras as well and it's why the ASC handbook has guidelines for panning rates. The only way to truly eliminate it is to use higher frame rates, but the drawback of that is it gives things the dreaded 'video look' - hence the recent complaints about the look of the Hobbit when displayed at 48fps.
 
Upvote 0 Downvote
You must log in or register to reply here.
Back
Top