XDCAM EX motion stuttering.

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Has anybody else seen any stuttering motion footage from the EX when shot at 24p?

We took one out for a test drive and shot a commercial 1080 24p, and upon viewing footage, it looks like the motion has stuttering. It's very subtle, but it's noticeable. Sort of like field sequential order problems or subtle acid trails.

I didn't have much time to study the manual, so I'm not sure if that's the way the camera renders motion in 24p, or if I did something wrong in the settings (like the first time I shot with the DVX in 24PA and couldn't figure that one out either...).

Still images look stunning, but the motion is a killer.

Any ideas?
 
Please post..
I've got over over a dozen hours of EX1 24P footage and have never seen this.
Maybe a problem with that camera...You're the first to report this.

There's plenty of 24P clips online now.
 
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Perhaps I was just being too critical of Sony. It looks like it's just how the EX1 processes motion. We did a a/b comparison between the HVX and the EX in 720.
After tweeking the shutter, we were able to get a motion image that was more pleasing than the HVX.
 
Are you saying that, for the same shutter on the HVX, you had to sort of "match it" on the EX-1? I had a thought about this the other day, that the same shutter speed that you would use on an HVX would have to be changed on the EX-1 to produce similar motion rendering.
 
The default settings on the EX were not what I would consider optimal (personal preference)

Basicly the HVX looks great out of the box but...

The Sony can produce a better picture. You are going to have work the settings and spend some time color correcting. The motion rendering reminds me of the old XL1 in "movie mode"
 
What did you adjust in the EX1, to make it look better?

I am curious because I was under the impression that cameras did not render motion, but simply recorded it.

Did you narrow the shutter angle, or adjust something with the color to change the look of the motion blur?
 
I think that's what he did. Change the shutter angle until it looked pleasing. And I totally get what he means about the XL1 motion rendering. I dunno the TECHNICAL term for it...

But an H1 looks completely different to me than an HVX when both are set to 1/48th. Not the same motion at all.
 
Kholi I get your point regarding the slight difference in look.

But is this simply a shutter speed thats too high? Anything around 1/90 (more as you go higher) or above will add a stutter effect on ANY camera at 24p.

j what shutter speed were you using?
 
Not certain, we had to tweek it a lot before we got a look we liked, but gave the camera back to the rep.

BTW, we were monitoring it on a sony tube monitor. That really help show the differences in motion as opposed to a flat-screen.
 
j said:
Not certain, we had to tweek it a lot before we got a look we liked, but gave the camera back to the rep.

BTW, we were monitoring it on a sony tube monitor. That really help show the differences in motion as opposed to a flat-screen.
Click to expand...

I see. From original sounds like nothing more than the stacatto effect of a high shutter speed/angle and the effect is the same on any camera. There may be a very mild perceived difference because of camera but its always going to be 99.9 % similar.
 
It seems to be that the camera shutter goes to 1/24 when the shutter switch is "off". That's the look that was unpleasing. It doesn't make sense, but everyone who saw the footage said it looked jittery. I'll try and post some footage once the editor gets me some. Once we got the shutter around 1/50-1/100 it started to look better.

Again I wish we had more time to test the camera before we had to give it back.

The monitor was a sony multiformat trinitron, BVM D20F1U. We checked it in 1080 and 720.
 
Sony's "Shutter Off" setting corresponds to how other professional broadcast cameras do it -- when you say "shutter off", you get no electronic shuttering at all; so at 24fps, it's 1/24th, at 60i it's 1/60th, etc. That's different from how the DVX/HVX do it; when you choose "shutter off" on them, it's 1/48th or 1/50th (in 24p) or 1/60th (in 60i).

So -- best to actually select the shutter speed you want. If someone's trying to compare "shutter off" to "shutter off", you'll find the EX1 a stop faster and blurrier than the HVX, because they wouldn't actually be using the same shutter.
 
To add to what Barry said, I think we all find the 1/48 shutter (for 24p) most pleasing because that is what films cameras have used for most of film history (actually, older cameras used 170° or about 1/50 second because they needed 190° of the shutter cycle to pull down the film and register it). This type of shutter shows us 50% of the motion and hides the other 50%, so each frame skips forward a bit from the last

But I wonder if ultimately "shutter off" will start to please us more - it shows us all of the motion smoothly in the form of a longer blur, with no gaps frame to frame.

For now, it looks oddly stuttery and blurry.
 
i noticed this also. out of the box, the ex-1 looked "video-ish" but this was simply due to the shutter being off. without knowing how it differs from the dvx/hvx, i ended up settling on 1/48 because it ended up looking better for shooting in 24p.
 
matthew77 said:
But I wonder if ultimately "shutter off" will start to please us more - it shows us all of the motion smoothly in the form of a longer blur, with no gaps frame to frame.

For now, it looks oddly stuttery and blurry.
Click to expand...


1/24th just isn't sharp enough. I do it every now and then on my HVX when I have an adaptor on and just need the light, but rarely with a lot of motion in the frame.

24FPS replaced 18FPS as the standard when sound came in. It was the slowest a projector could run at the time without an audible wow and flutter. Not because it was the prettiest frame rate. But 1/24th definitely crosses the thresh holdhold of looking good.
 
My point, exactly Tim. For now 1/24 is not sharp enough, but I wonder if that will always be the case.

This is the first time in the history of filmmaking that a 360° shutter is possible. the 180° shutter was the largest one could go (with a few exceptions) on film cameras for purely technical reasons - sharpness was not a consideration.

I think that we will grow more accustomed to the open shutter over time and may even ultimately prefer it. It might be that we'll like 48p or 60p with an open shutter because 24 is too slow. But I think "no shutter" is in our future.
 
Hey guys... I am a total noobie to video, and I have been researching extensively over the past 2 weeks on which camera to buy. The EX1 is attractive in many ways. However, looking at sample video, most of the EX1 samples I find have some sort of jerky stutter. An extreme example is here: http://www.vimeo.com/682012. It seems much less noticeable in other EX1 samples, however I seem to notice it when a camera is obviously on a tripod and not moving, but there consistent movement in the objects being shot (moving water, cars, clouds, etc.)

I have do not recall noticing this in video samples of the HVX or the Canon XH-A1. Has anyone else noticed this kind of thing in the EX1? Is it simply a setting issue? Perhaps a known issue with the EX1? Or, am I just going crazy from trying to make up my mind and looking at too many video samples?

Lastly, if you have EX1 samples showing moving objects without camera movement, please share them with me as I'd like to see if I can catch the little glitches in the matrix I am seeing.

Thanks!
-sutton
 
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