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I haven't checked the footage frame by frame but I donot think Im missing frames. As far as the computer is concerned here is what I have in my machine, I dont think its a slow machine.
NVIDIA GeForce 8800 GT video card Model Name: Mac Pro Model Identifier: MacPro3,1 Processor Name: Quad-Core Intel Xeon Processor Speed: 2.8 GHz Number Of Processors: 2 Total Number Of Cores: 8 L2 Cache (per processor): 12 MB Memory: 10 GB Bus Speed: 1.6 GHz |
Has anyone heard of "rolling shutter" (I'm sure everyone has)?
Is this what is being seen? The same problems with CMOS camcorders plague CMOS DSLRs. |
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I think u r having a low shutter speed prob. I can steadicam with the 5D/7D with no issues unless I run. Try cranking up the shutter speed. If u r doing 30p, tune the shutter to 60 and have a go. It should help.
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stutters when panning
I shot some footage on Saturday of swans and when playing back, I noticed stutters that seemed to be very equal in spacing and length. I remembered reading something about this last year, and when I checked back I found this thread and followed advice regarding shutter speed and IS on 70-200 f2.8L IS and 24-105 f4L IS and still the problem remains tonight- is this something to be concerned about, regarding my 5dmkii, or simply my poor panning technique or an idiosyncrasy of the cmos sensor. Manual everything on the camera. Thanks in advance, Bill. Sandisk Extreme 60MBs brand new 8GB
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Bill, make sure your IS is always off! See if that helps :-)
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I think this discussion will be enhanced by posting some of the video for download or to watch.
It is tough to describe stutter or judder. |
maybe a solution?
Guys, I think I may have stumbled on a reason for my "stutters"- when I went to cut movie to upload, the only editing package I have is zoombrowser, and the little "cut movie" screen came up and the video played back perfectly-when I made it full screen the shudders returned. Maybe my machine is just not up to playing back raw files, so my next move will be to play them on a more powerful machine and see if that does the trick- as is painfully obvious I am a complete novice at this video stuff, but I avidly read this forum and I will get better! Thanks for your advice, Bill.
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Ah yes, the age old graphics card issue... very well could be that your graphics card isn't handling full screen playback well. Let us know what your findings are!
Best of luck man. |
Four-frame stutters
Today I did some test shooting and got four-frame "stutters" during a walking pan. The image freezes momentarily on the LCD and the lens (24-105 f/4 IS) made a "squeak" like the IS or USM servos twitching.
The freeze/stutter was fairly repeatable, happening at roughly the same places during the walking shot, whether the lens was in AF or M, IS on or off. In all cases, I'm starting to come 'round a corner from an area of relative darkness to an area flooded with sunlight. Playing back the camera-original file frame-by-frame on a MacBook Pro shows that each stutter consists of a single frame repeated four times, repeated right down to the captured chroma noise. There is audio through the freeze (e.g., the IS servo) but the servo "squeak" was not recorded. 30 fps 1080, 5D Mk II firmware 1.2.4. 8 GB Lexar 133x (20MB/sec) CF card, which may be the root of the problem; faster, UDMA-capable cards are said by some to be a solution. How does this match up with what you're seeing on your stutters? |
Adam -
My cam did the same thing; "the four frame stutters". My cards: Lexar 300x 8gb, clean and completely formatted. Len's utiized: 16-35, 70-200 (IS was off when shooting). This is not the film panning "Judder"; but like you stated actual missing or repeating frames, hence "Stutters". This happens at all camera setting combination's. Maybe the new firmware that just was released will help resolve this. |
Looks like it's the aperture self-adjusting that causes this stutter
I've done more testing (with firmware 2.0.3 installed) and have more info.
I tried with a Sigma 50mm f/1.4 prime, and got the same "squeak" (or "chunk") sound--turns out it's the aperture stepping from value to value. If I have the camera in P or Tv modes, I'll get the squeak/chunk whenever the aperture steps, and I'll get a four-frame-freeze whenever it happens. If I'm recording, I get it recorded, minus the sound of the aperture servo; if I'm just in live view, I can see it freeze on the LCD. So far, I haven't been able to make it happen in Av or M modes. If I manually change the aperture, I'll both see it and hear it in the recorded clip, but I don't get any drops or freezes. If this behavior is consistent, then what I saw in my tests yesterday wasn't the panning per se that caused the stutter, so much as the exposure change panning between lighter and darker areas causing the aperture to auto-adjust, and for whatever reason the camera skips three frames of new data when this occurs. It's just as well that I plan to shoot in M mode, eh? |
Adam,
I would recommend shooting Tv mode after pressing the AE Lock (*) button. That should stop your aperture from hunting around. I see this as the "News At 11:00" mode... I'm driving along. I see something newsworthy. I grab the camera. Set the WB to the nearest preset. Choose Tv. Select 1/50 or 1/60 as appropriate. Record. Press (*) to lock the exposure. Use exposure offset, if needed. Sell footage to national news outlets. Use proceeds to buy additional camera gear. ;) |
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I've verified that this is NOT stutter, when stepping through the original footage in the 5D2 mov file, there were two different spots where a single frame was repeated for 3 or 4 frames. I've seen this before on occasion, but I thought it was always related to aperture change. Last night though, I swear I had exposure lock on (and my metering timer is set to 30 minutes), but maybe it reset after goofing with it right before she came in, can't be sure. But, it's a little troubling for me -- I sure hope it's only an aperture thing. One thing is for certain, and I've seen other references on the Net, the 5D2 is definitely capable of repeating frames. Now I'm sure a lot of the stuttering reports are bad playback systems, but I for one have seen the repeated frames with my own eyes while stepping frame-by-frame. Anyone have any other experience with this, insights? |
Tom, a quick test to see if it is your PC/laptop that is not fast enough and causing the problem viewing full-rez 5D files is to edit a short clip section and then convert to 720P. If the 720P clip then runs smoothly it is more than likely that you need a more powerful computer.
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