GH2 official discussion thread

g.l said:
I suspect a lot of you who see this with footage with relatively slow motion (as your pan is) are actually having codec issues, and/or an underpowered CPU, resulting in dropped frames during playback. Or if you're viewing online, you're not getting a smooth download, resulting in missing frames.

The Vimeo footage you linked plays fine here on my quad-core PC. There is a very very sutble judder that comes from using 24fps - but it is barely noticeable unless you know what to look for. If you are seeing major judder or jerks then it's something else on your system.
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i think ken means the subtle judder. he said he also watched it on plasma screen
 
Ken7 said:
Roei, I guess the things that drives me nuts is that I do see panning (at about the same speed I used) on other 24p clips and don't see this degree of stutter. Of course I don't know what, if anything, was done to these clips in post since most are not available as native m2t clips. Perhaps something is done in post that removes some of the judder.

Roei, if you can, would you direct me to another clip that you feel shows this degree of stutter? Thanks much!
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Try shooting again with a 1/24 shutter (or nearest too it). You will get more motion blur, but that helps fill in the missing motion information and will look smoother.
 
Bingo Roei. That's what I was going to say to g.l. I see exactly the same stuttering motion on my plasma, so it's not a codec issue. Additionally, I'll watch 24p clips that look much smoother than mine even though it's shot at the same shutter speed.

Take a look at this clip shot by another GH2 owner and notice that beginning at about the .33 second mark, he pans rapidly and still there is little stutter relative to mine. He too used a 1/60 shutter speed (watch the trees in the background).

http://vimeo.com/18377339
 
Ken7 said:
Take a look at this clip shot by another GH2 owner and notice that beginning at about the .33 second mark, he pans rapidly and still there is little stutter relative to mine. He too used a 1/60 shutter speed (watch the trees in the background).

http://vimeo.com/18377339
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It looks like it has more motion blur to me. I would guess that either you weren't using 1/60, or that video wasn't shot at 1/60. Try shooting at a longer shutter speed.
 
mmmm... the sliding people judder the same.. the trees.. well we need to have some more opinions from users :)
 
Another possibility, the trees in Ken's video are sharpened. The difference could be compression artifacts caused by sharpening, as this creates harder contrasts between edge pixels. It's possible the codec simply doesn't handle that too well during motion.

Would be worth trying out, if true you would be better off shooting with less sharpening, and do it in post.

EDIT: Just to confuse things more, most LCDs really don't like high-contrast pixels moving around. They are tuned for lower contrast transitions between pixels (which is what you usually get in video).

An extreme example of that is a 1:1 pixel checkerboard pattern like this one. Be sure to view it at 100%, then try scrolling it. On an LCD it will flicker like crazy. Wouldn't flicker on a CRT at all. So again, heavily sharpened images will flicker more on LCDs than they should.
 
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Briefly I thought Barry_Green turned into Super Saiyan... :)

24p is a choice... but it's here to stay for practical purpose. More consumers wanna watch in 24p cinematic mode. Sometimes the jitter could happen because a player can't handle playback load. A frame in 24p usually contains more data than a frame in 60i. Gotta use a playback app with GPU acceleration preferably on HDTV with 1080p24 cinematic mode support. On computer screen with 60Hz or 120Hz, of course it will jitter more.
 
If the refresh rate of an LCD screen, be it TV or computer monitor, is NOT a multiple of the frame rate - there will always be a visible stutter. So 60Hz or 75Hz or 100Hz refresh rates will stutter 24p footage, 120Hz - will not, since 24*5=120.
 
g.l, I know for sure I was shooting at 1/60 (shutter priority mode) and the clip from the other guy shows it too was shot at 1/60. So I don't think that was the issue.
 
zigizigi said:
If the refresh rate of an LCD screen, be it TV or computer monitor, is NOT a multiple of the frame rate - there will always be a visible stutter. So 60Hz or 75Hz or 100Hz refresh rates will stutter 24p footage, 120Hz - will not, since 24*5=120.
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That might explain it to some degree since my plasma would be @60hz as would be my computer monitor. The contradiction though are the other clips I play on this same equipment that stutter far less.

G.l, I used the 'cinema' mode at default.
 
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try shooting manual mode on 1/50,
While focusing on a near object and pan with the trees
Less focused in the background.. not as sharp as your
Earlier clip
 
Barry_Green said:
People repeat 1/48 as if it's gospel, when in actuality it isn't even that widespread. 180 degrees is not sacred.
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I agree with you, 1/48 second shutter speed is not a magic number. I was using it not as a precise number, but as a shorthand reference to the 180-degree rule. In practice, I think there's a range of shutter speeds from around 1/40 - 1/60 that produce a cinematic sense of motion blur. And if you shoot at the same shutter speed, you'll get the same amount (rather than degree) of motion blur regardless of whether your frame rate is 24, 25, or 30fps.

Barry_Green said:
It's really so simple to test. Get a DVX100. Shoot a scene at 60i, with 1/60th shutter. Then shoot the exact same scene at 24p, with a 1/60th shutter. One will look a whole lot more filmlike than the other. It's night and day different.
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I agree with this too, but to my eyes, the dominant factor is the 60hz interlacing rather than the difference in underlying frame rates. If the first test was at 30p rather than 60i, I'd probably prefer it to the choppier motion of 24p. Perhaps I've become oversensitive to interlaced video after watching a bit too much DirecTV on a crisp LCD monitor...
 
Screenhorn said:
Nobody from the EU here? ;-)
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Hi Tom,

I do not understand the problem.
You can record 29:59 as often as you want.

Once recorded 29:59, the camera stops and you are ready for another 29:59.
You can do it as often as you wantr or untill the card is full.
On a 16GB card more than 4 times, as it records about 2:05 of AVCHD Material.

You can PM me in german if you like.
 
I have a couple of 14-140 and 100-300 lenses, and I have compared them using a variety of subjects. In all of these “tests”, the results are consistent with those below. I was seeing this in video taken by the 14-140 and 100-300.
The 100-300 at 136mm, f4.4 is much better than the best of the two 14-140s at f8.0, the best aperture for this lens at 140mm. The 150-300 attached to the same camera at the same place on the same tripod, at an indicated focal length that is shorter (136mm vs 140mm) gives a much larger image (it crops farther into the image) than the 14-140 at 140mm. It seems curious that either both 14-140 lenses or both 100-300s appear to marked incorrectly as to focal length. I wish there was a faster lens in this very useful 14-140 mm focal length range, with image quality comparable to or better than the 100-300. I wonder if Panasonic will make a new lens, perhaps one from Leica, available now that the AF100 is shipping?

Here are a couple of crops from the two lenses. In the Tifs at 100 percent, the detail difference is striking. Has anyone else noticed these differences?
100-300, 136mm, f4.4
http://gallery.me.com/billh96007/100323/New-GH2,3507,136mm,f4.4-53_1/web.jpg?ver=12940992730001
14-140, 140mm, f8.0
http://gallery.me.com/billh96007/100323/New-GH2,1690,140mm,f8.0-051_1/web.jpg?ver=12940992680001
 
The detail of the 14-140mm lens drops off from 100mm-140mm, any lens with a large focal range always makes compromises in quality at either end of their range.
 
Also, the maximum focal length is reached only at infinity focus. It drops at closer distances. This is a common phenomenon with zoom lenses.
 
Is there no way to turn of that shutter noise when taking single shots? I see a new menue : BEEP : E- shutter volume which sounds promising but seems to only permit to turn it off during Auto Bracket.
I would at least like to turn down the volume for single photos...or turn it off alltogether. I dont like this fake shutter sound with the mirror clicking although I understand its existence...
 
It is no fake shutter sound.
There is a shutter moving twice when you take a picture.
This is what you hear.
 
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