D3s Quality of Saved Frames of Video vs Quality of Stills

Discussion in 'Nikon' started by jaina, Sep 5, 2010.

  1. Hi,
    Would like to get inputs from experts on this...what are the pros and cons of taking videos and then saving frames versus just taking stills?
    I want to experiment with the video+frames but would like to go into it informed about the compromises if any...
    Thanks
    jaina
     
  2. Non an expert...You can print larger from stills if I'm not mistaking. Also, does D3S have AF in Vmode yet? Last time I heard, nikon video suck butt compare to Canon and Sony. These two are big hurdles...
     
  3. Leslie is not totally correct I'm afraid. Setting the Canon vs Nikon debate aside (which Leslie was wrong to initiate here), capturing frames from a video vs capturing a still has ONLY to do with resolution. Even the highest resolution video captured from a DSLR these days is of a significantly lower size than the equivalent still captured by the same camera. Therefore, a still will ALWAYS have more data, higher resolution, more depth, density, etc, etc. Furthermore, the still will be uncompressed (assuming you shoot RAW or TIFF) data compared to the movie frame which will be processed and compressed information (thereby of an even lower overall quality).
    As for autofocus, NO DSLR has continuous AF in video mode. You have to constantly manually adjust your focus (if your subject is moving in such a way as to require focus adjustment - i.e. not parallel to the movie plane). Still, this has NOTHING to do with picture quality.
    Therefore, if you're looking to produce high quality images, stick with stills. If you want to shoot video, go ahead. You can maybe expect some average quality frames to come out of it, but nothing remotely resembling a proper still.
     
  4. capturing frames from a video vs capturing a still has ONLY to do with resolution​
    It's not only that (or continuous AF) I'm afraid. It's also about speeds, exposure time and frame speed. A frame from a video can not be captured with long exposure time like 10 seconds for example (or even 1/15 sec). Marios didn't mention any "pro" (only "con") about video frames. NO DSLR can shoot 24 fps unless it's video
     
  5. Leslie, the user's manual says that AF is possible in the tripod mode but not in the handheld mode after recording starts.
    Marios, I guess with your explanation, I will stick to using this for just stills since thats what its best at ...and use an additional video camera for the videos.
    Thanks
     
  6. John, that's a good point about 24fps capability.
    Am also wondering if saving frames from videos taken with regular camcorders is equally easy...
     
  7. capturing frames from a video vs capturing a still has ONLY to do with resolution. Even the highest resolution video captured from a DSLR these days is of a significantly lower size than the equivalent still captured by the same camera. Therefore, a still will ALWAYS have more data, higher resolution, more depth, density, etc, etc. Furthermore, the still will be uncompressed (assuming you shoot RAW or TIFF) data compared to the movie frame which will be processed and compressed information (thereby of an even lower overall quality).​
    Doesn't all that just means, in four words, one can print larger (which I stated), Marios? Are you a nikon fanboy? Or just incredibly dense?
    You have to constantly manually adjust your focus (if your subject is moving in such a way as to require focus adjustment - i.e. not parallel to the movie plane). Still, this has NOTHING to do with picture quality​
    I don't know about you but nothing in focus and everythings in constant blur degrades the picture quality a whole lot for most everybody. Even if, say, you have 50MP of "depth", "density" of "uncompress" data, right? How about watching your favorite film/video out of focus, Marios?
    Leslie is not totally correct I'm afraid. Setting the Canon vs Nikon debate aside (which Leslie was wrong to initiate here)​
    Why am I wrong to initiate Canon vs. Nikon debate here? What if the OP has $20,000 in the bank and he/she want to switch brand just because of videos? Better yet, the OP maybe able to afford both brands? Doesn't she/he has a right to know what brand does what better? What has better videos? a $2500 D700, a $5000 D3 or say a $800 Canon T2i? Nikon is working hard on their video capability (with D3100) but Canon still has the edge...just like Nikon is leading in the high ISO low noise front.
    As for autofocus, NO DSLR has continuous AF in video mode.​
    You must have missed the recent Sony cams. AF in video modes, 10 FPS etc...
     
  8. 1080 video will give you an image approximately 1920×1080 pixels in size.
    720 video will give you an image approximately 1280 × 720 pixels in size.




    Obviously neither has a high pixel count. Both will give you a somewhat reasonable 4" x 6" print (better than nothing). Smaller is better when in comes to printing video frames.
    "compromises"??? If you need a high quality still, don't shoot it with video or with a video camera.

     
  9. Leslie, the user's manual says that AF is possible in the tripod mode but not in the handheld mode after recording starts.​
    Probably due to it's phase based AF mechanism. The mirror needs to drop for it to AF. With Liveview/video mode, AF is disallowed. To be honest, the techinicals are beyond me, Jaina. Video on some compacts are better/easier than DSLRs...
     
  10. Hi Leslie,
    Not only are technicals beyond me, manipulating all the various parameters for each new situation is also something I am struggling with! So all of you here are certainly way more knowledgeable than I am!
    Elliot,
    "compromises"??? If you need a high quality still, don't shoot it with video or with a video camera.
    you may not need to compromise, but me at 5'2" I get very burdened with the stuff I have to carry around. I love taking stills, but sometimes - like in Lion Dance performances on the street, I'd also like a video capture and it would be nice if I didn't have to lug along a video recorder AND a still camera IF it were possible.....therefore I asked this before I go out and experience the results for myself....
    Elliot, Leslie, Marios, thanks for all the info - I have only Nikons, but its always good to know about the rest.
    Thanks again.
    jaina
     
  11. Okay...I apologize for my "suck butt" and "nikon fanboy" in my previous comments. Rough day, today...
    Jaina, best of luck to you...if haven't, check out the recent Sony A55/33 if you want to intergrate video/stills
     
  12. The resolution of a 720p frame is only about 1MP, compared to 12.1 MP for a still shot from the D3s. There's also a format change of 16:9 vs 3:2. You can print about 4x as large with the still than a frame grab.
    You can shoot a still with a D3x in the middle of a video sequence. However this causes a brief interruption in the video clip, which may not be desirable. This does not occur when you grab a still with a conventional video camera, which simply saves whatever has been captured in buffer memory from video at the time.
     
  13. ShunCheung

    ShunCheung Administrator

    Still frame capture from D3S video will give you 1280×780 JPEG basic (lowest quality) images, which is about 1MP. It is fine for web display and actually exceeds what we typically post on our Wednesday image threads, but it is not good enough for most other applications.
     
  14. "me at 5'2" I get very burdened with the stuff I have to carry around." A small P&S will shoot excellent HD video and easily fit in a small pocket. Or if you are shooting video with your main camera, you can get great high resolution shots with the P&S that will be noticeably better than a frame pulled from any video.
     
  15. There will also be a bit depth difference and the fact that this frame is compressed beyond that. As an overview, intra-frame video has an actual frame for each frame of video. Most of todays video recorders use an inter-frame method of recording video. Again, in a nutshell, you have around 29.97 frames of video. With intra-frame this means you have 29.97 actual frames. With inter-frame (which is what a DSLR will use) has TWO frames and the rest is fancy math recording the motion difference between each of the two actual frames. So most of the "frames" within a DSLR video are just mathematical "guesses". This is a BIG difference between an actual STILL frame.
     
  16. With Liveview/video mode, AF is disallowed.
    Contrast-detect AF works in tripod-based live view mode (in the D3, D700 etc. at least) and I believe also during video capture (when in tripod mode) in the D3s (if I understood the answer to this question in Nikon's European customer magazine correctly). As far as I know, Canon 5D Mk II doesn't support autofocus during video capture at all. Of course, Nikon's implementation of contrast-detect AF isn't very good yet.
    You can shoot a still with a D3x in the middle of a video sequence.
    The D3x doesn't shoot video at all.
    There will also be a bit depth difference and the fact that this frame is compressed beyond that.
    The amount of data stored per individual frame is very small. There is a severely limited shutter speed range, you can't use flash, etc. I think the idea of pulling stills out of video has very limited applications only.
     
  17. I can confirm that when in tripod mode the D3s does indeed autofocus while filming. You do this by pressing the AF-ON button beside the main comander wheel. However it only works if there is enough contrast on the subject, and it is quite slow. If there is not enough contrast on the subject or if the lighting is poor then the lens hunts until it finds what the camera thinks should be in focus. It doesn't always pick what you want to be in focus.

    In situations where there is enough contrast it does in fact find a more acurate focus than I personally am able to do by manually focusing, at least, it does it faster than I can. But in the opposite situation where contrast is poor, it is useless.

    As others have stated, a still capture from the video file is a little less than 1MP, so the resulting picture will be of drastically less resolution than a normal exposure of 12MP. If you're interested in capturing some kind of fast happening action then you are far better served shooting at full speed 9fps or even a 5MP picture in DX mode at 11fps. The increased buffer of the D3s allows for a very large number of frames to be captured at this speed before it slows down, especially if you're shooting jpgs.
     
  18. Wow, so many replies, while I was sleeping.....will process them all with the help of some caffeine now!
    jaina
     
  19. Leslie,
    Thanks - I will look at the Sony for the future.
    Edward,
    You can shoot a still with a D3x in the middle of a video sequence. However this causes a brief interruption in the video clip
    How can I do that? Thanks​
    shun
    It is fine for web display and actually exceeds what we typically post on our Wednesday image threads, but it is not good enough for most other applications.
    that's great news. the compromise won't feel so bad now..​
    Elliot, - I think your suggestion sounds good - its not that terrible to carry a compact P&S!
    John, Ikka - thanks for the detailed explanations - I will read up more on the subject.
    Hamish, I will experiment with the 'tripod' (which is another burden for a lazy 5'2" woman) and the AF-on - I read about that in the manual...but have yet to try it. Will also try to cheat by just 'setting' it to tripod ...but using it as handheld...
    All,
    Thanks for all the inputs - I think the conclusion is that the image quality will definitely suffer in one way or another in the frame saved from a video compared to a still. Will either prioritise or add on a P&S.
    Thanks
    Jaina
     
  20. Will also try to cheat by just 'setting' it to tripod ...but using it as handheld...​
    Exactly! You don't have to use a tripod to shoot in tripod mode :)
     

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