GH2 official discussion thread

guys- the issue of 24p stutter, is well known. if you watch films, you'll notice a certain stutter. that point is understood and concerns on how you shoot etc... ok?

now- about the pan stutter on Larrys clip - mickee13 also sees it, so it's not just my monitor. i'm sure a lot of other viewers will also see it.

now for the main problem - Ken is asking whether you can make some kind of post "smoothness" to minimize the "regular" stutter (though once again, the pan shot DID stutter like my clips)

for my end, i DO notice my monitor judders more than viewing on my projector, which is showing a lot smoother motion, like it should be, so there are some monitor issues that need to be cleared out
(60hrz monitor will show more judders than 24p native viewing equipment - like my projector)

ok, now let's keep on the endless unanswered questions :)
 
Ken, the workflow is listed on this link:

http://www.vimeo.com/18333182

To answer your question, no, the 24p clips straight from the camera do not have a stutter. And mickee, you are right, the pan is the worst type of shot for the 24p but great shot to test with. I went back and looked at it and if I focus on the masts as well, I do see a very, very slight stutter, but who else would be focusing there when the man walking naturally draws your eye?

I still think for this kind of panning shot that you are all discussing, 720/60p on the GH2 will be the most smooth. But the thing that I am excited about is that before this workflow, I would bever have considered 24p because ALL MOTION on every 24p video I have seen has the stutter. Now, on my test videos, the people walking, car going by, skateboarder, people on bicycles, etc.. all looks smooth. I didn't think this would be possible.

So, my question for all of you, beides the panning shot, how does all of the other motion look to you?

And did you look at the 1080p stream? That one is here:

http://www.vimeo.com/18345432

Thanks!
 
at least we all agree that there is a stutter to some degree on this pan shot :)
Larrys, can you upload an old clip of yours that has a lot of stutter? just to understand the difference?
 
mickee13 said:
There are so many variables, shutter speed, dof, does the playback device have motion processing enabled etc etc. There are many interesting articles out there, including this one:
http://www.projectorcentral.com/judder_24p.htm
Click to expand...
Thanks, mickee13, that was a very informative article on the history of 24p film production. One point I found interesting is how motion picture projectors display each 24p frame twice, separated by a brief black frame, for an effective frame rate of 48p to reduce flicker. In contrast, modern video displays produce a seamless stream of images without blacking the screen in between frames. I think the absence of flicker makes the differences between 24p, 25p, and 30p much less noticeable. It seems to me that shutter speed is a more significant factor in producing cinematic motion blur than frame rate.
 
Could this shutter be caused from using a 1/50 shutter speed rather than a 1/48 shutter speed? Since you notice it on every device you've had that records in 24p?
 
Dazza said:
Could this shutter be caused from using a 1/50 shutter speed rather than a 1/48 shutter speed? Since you notice it on every device you've had that records in 24p?
Click to expand...

Good question Dazza, but I don't know the answer to it. Since I've never had a 1/48 speed to choose from, 1/50 or 1/60 had to do.
 
lpowell said:
Thanks, mickee13, that was a very informative article on the history of 24p film production.
Click to expand...

More interesting than this article (which is probably full of inaccuracies) and the many others like it are the hundreds of comments below that probably have even more informational value. 24p just like interlacing really is a relic from the distant past and it's probably time to move beyond to smoother frame rates. The problem is that we've all become used to it. When I see a blu ray being played back on a monitor with one of the motion smoothing algorithms enabled I can't stand the sight of it....it's just too smooth and looks terrible. On the other hand, I hate seeing stutter also. It's a fine line to get motion that's appealing.
 
Dazza said:
Could this shutter be caused from using a 1/50 shutter speed rather than a 1/48 shutter speed? Since you notice it on every device you've had that records in 24p?
Click to expand...

I shot something recently with my GH2 and used shutter speeds from 1/40 to 1/60 and there was maybe the very tiniest of difference in motion blur. You really have to look hard to see the difference so I highly doubt there is any real difference between 1/48 and 1/50th. When I first starting doing my pans I had to slow them to an absolute crawl to get away from stutter, even the slowest of my pans has some stutter if you look for it. It is less noticeable when I play it back on blu ray or on my monitor from the high bit rate MP4 render, so I wonder if 24p stutter does get amplified with web video. I do agree that motion within the frame, stuff like people walking, smoke, stuff like that does have an appealing motion compared to higher frame rates that start to look a little to smooth to me. Having said that, I've watched some great 720p/60 stuff....so who knows. Content is king.

Here's my 24p test with lots of slow pans.
http://vimeo.com/18315611
 
mickee13 said:
And there lies most of the answers to 24p footage. If there was a shallower DOF to that shot with less contrasty surroundings you would have seen no stutter at all. I see the same stutter on that pan as most native 24p stuff. It is less distracting with a moving subject kept relative in the frame. Your backyard footage is a pretty fast pan for 24p with deep dof, high contrasty image.....the worst possible scenario.
The whole 24p motion subject is a constant never ending debate on the internet. Just Google "camera panning 24p" and you will find thousands of posts from all different capture devices and playback monitors with varying results. There are so many variables, shutter speed, dof, does the playback device have motion processing enabled etc etc. There are many interesting articles out there, including this one:
http://www.projectorcentral.com/judder_24p.htm
Click to expand...

Good article and a good explanation why I've always hated the look of 24p. For whatever reason (probably the frame doubling of the movie projector spoken of in the article), judder in today's movie theaters has never bothered me...certainly nothing even close to the judder I see in 24p videos from DSLRs.

I'm extremely happy with the 1920X1080 60i output of the GH2 and welcome it with open arms! :happy: It looks almost as smooth as the 60p output from my Panasonic TMV700. But the GH2 beats the 700 in terms of color fidelity, exposure and DOF.

Mickee, I suspect you're right about the small differences in going from 1/40-1/60 as it relates to motion stutter.
 
Thanks, Peter, for the link to another article that confirms a somewhat surprising conclusion:

The "film look" is actually 48fps!

720 or 1080 at 50p is likely the closest that fixed-rate digital cameras will come to duplicating the frame rate of a movie projector. Unfortunately, this frame rate would strobe badly with 60hz lights in NTSC countries. Yet another good reason to stage location shots in Europe...
 
lpowell said:
Thanks, Peter, for the link to another article that confirms a somewhat surprising conclusion:

The "film look" is actually 48fps!

720 or 1080 at 50p is likely the closest that fixed-rate digital cameras will come to duplicating the frame rate of a movie projector. Unfortunately, this frame rate would strobe badly with 60hz lights in NTSC countries. Yet another good reason to stage location shots in Europe...
Click to expand...

ok, so you're saying that a film shot on 24p with GH2 (or red, for that matter) screened digitally in a theater will judder more than classic film. right?
 
roei z said:
ok, so you're saying that a film shot on 24p... screened digitally in a theater will judder more than classic film. right?
Click to expand...
Not the judder, it's the flicker that would be different. Since digital projectors don't black out the screen briefly between each 48p frame, the 24p digital projection would lack the 48fps flicker of an analog film projector. But as we all know by now, panning at 24fps must be done very slowly to avoid juddery on-screen movement.
 
lpowell said:
The "film look" is actually 48fps!
Click to expand...

I think you're confusing display refresh rate with footage frame rate. A cinema film projector refreshes at 48Hz (to combat flicker) - but that doesn't magically give you intermediate frames in your footage. You are still recording and playing back movement at 24fps, that is the limiting factor (and the 'look').
 
g.l said:
I think you're confusing display refresh rate with footage frame rate. A cinema film projector refreshes at 48Hz (to combat flicker) - but that doesn't magically give you intermediate frames in your footage. You are still recording and playing back movement at 24fps, that is the limiting factor (and the 'look').
Click to expand...

that's more like it :)
 
g.l said:
I think you're confusing display refresh rate with footage frame rate. A cinema film projector refreshes at 48Hz (to combat flicker) - but that doesn't magically give you intermediate frames in your footage. You are still recording and playing back movement at 24fps, that is the limiting factor (and the 'look').
Click to expand...
No, I'm not confusing the two factors, I'm claiming that 48fps flicker is the actual film experience. What makes it 48fps is not the movement within each frame, but the fact that there is an interleaved black frame between each video frame. An underlying 24p frame rate is not really essential. If it were, we'd never be able to tolerate the distorted cadence of telecined 24p films on DVD.

The other major factor is the 1/48th second shutter speed, which determines how much motion blur is seen during panning and object motion. I suspect this is far more important in creating a filmic look than the underlying frame rate.
 
Has anyone figured out a way to make aperture the priority for the manual exposure settings? I'm talking about how you have to push the dial tow toggle between setting shutter speed and aperture. For video I'm almost always wanting to leave shutter speed constant and change aperture, but I keep changing shutter speed by mistake since that's the default. I can live with this but it would be nice not to have to remember to switch from shutter to aperture. Especially since I'm using c1, c2, and c3 for different iso settings...
 
lpowell said:
No, I'm not confusing the two factors, I'm claiming that 48fps flicker is the actual film experience. What makes it 48fps is not the movement within each frame, but the fact that there is an interleaved black frame between each video frame. An underlying 24p frame rate is not really essential.
Click to expand...

I think you're wrong. 24fps is mainly what the look is about. It is the unnaturally slow capture rate (compared to how we see things) that gives film/cinema it's slightly surreal, dreamy look, coupled with the fact that you have to move the camera & subjects slowly enough to make viewing enjoyable, and/or use enough motion blur to cover up faster movement. It all forces a certain controlled pace. 50fps gives you the look of video, not of cinema. Easy to try out.

Think about it this way - 24fps Blu-rays still look like film on 24Hz LCD (or even 60hz, ie. computer monitor) displays. 50fps video doesn't.

The other major factor is the 1/48th second shutter speed, which determines how much motion blur is seen during panning and object motion. I suspect this is far more important in creating a filmic look than the underlying frame rate.
Click to expand...

Try it.
 
g.l said:
I think you're wrong. 24fps is mainly what the look is about. It is the unnaturally slow capture rate (compared to how we see things) that gives film/cinema it's slightly surreal, dreamy look, coupled with the fact that you have to move the camera & subjects slowly enough to make viewing enjoyable, and/or use enough motion blur to cover up faster movement. It all forces a certain controlled pace. 50fps gives you the look of video, not of cinema.
Click to expand...
Sorry, but I think the fact that cinema is actually projected at 48fps debunks the 24p myth. If 24fps motion judder was a desirable visual effect, directors and DP's wouldn't go to such lengths to minimize it by restricting motion and pans on-screen. I tried playing a couple of Blu-ray discs at 24p on my HDTV and just as the article linked above described, the motion judder looked even worse at native 24p!

What looks filmic to me is the motion blur from a 1/48 second shutter speed, combined with narrow depth-of-field to isolate the foreground actors from the background, and projected in progressive frames without the curse of telecined interlaced jitter. What looks video to me is a deeply focused, lightning fast shutter speed with fake aliased edge-sharpening, displayed in a 60hz interlaced blizzard.
 
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