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More Jello issue on PAL (25p) than NTSC (30p) in 4k video

Discussion in 'Pro/Adv Discussion' started by John Lo, Aug 19, 2015.

  1. John Lo

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    Is there anyone use PAL (25p) to record 4k video in P3P? I hv done a not so scentific test for jello / jitters effect and realize there is a lot less jello effect when you record in NTSC (30p), especially when you do panning shot.

    as the sensor in p3p is similar to the sony mobile phone CMOS sensor. when you record video using mobile phone, it does not have the option to choose PAL / NTSC, normally either 30p / 60p / 120p. so, I am wondering if the sensor is native support PAL mode (50p / 25p)?

    will the p3 only native support NTSC video record and drop frame internally to PAL? that is why PAL mode is not so smooth / a lot of jitters.

    Any comment / guru help, pls.

    here is the example.

    25p:
    https://drive.google.com/open?id=0BzS3fJZH0ldcVlFSVlFDTUNiRzg

    30p:
    https://drive.google.com/open?id=0BzS3fJZH0ldcemZEODB5dEh4bzg

    renew test :

    I hv test the video playback on notebook monitor, 24" hdmi computer LCD and large tv for different refresh rate (50hz / 59hz / 60hz) , the result is the same above, 25p has more jello / jitters / not smooth.
     
  2. Daninho

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    There is always less jello in higher FPS, at 60 FPS there is even less.
     
  3. John Lo

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  4. Doug J.

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  5. John Lo

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    Doug J.. Sorry , I forgot to mention, All Video test using lowest shutter speed (25p/30p/50p/60p ISO 1600-3200) already, so the jello effect is not coming from high shutter speed.

    Also, i hv google that i may got some info about the sensor of P3 - sony exmor imx117cqt.

    (not sure wherther it is correct, if anyone knows , pls confirm and correct)

    http://www.sony.net/Products/SC-HP/cx_news_archives/img/pdf/vol_70/imx117cqt.pdf

    According to the document, Table 3, There is a mention of frame rate for 48p , 60p and so on, but no 25p or 50p! so I am coming up a big question, is the P3 PAL mode = NTSC mode + drop frame?

    If there is true, That explains PAL mode is more jello / jitter than NTSC mode and p3 is not native support PAL mode.
     
    #5 John Lo, Aug 19, 2015
    Last edited: Aug 19, 2015
  6. Doug J.

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  7. John Lo

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    Doug J., I hv set manual mode, indoor light is not bright enough already so i push iso (1600 - 3200) and keep shutter speed as lowest as possible. in hk, it was 5am.

    e.g. : 4K 30p : shutter speed 1/30 , iso 1600, WB 2700K
    1080p 50p : shutter speed 1/50 , iso 3200, WB 2700K
    ........

    By the way, if you hv p3 and u need the PAL mode, pls try it yourself and u will know the result. I am in latest FW version.
     
    #7 John Lo, Aug 19, 2015
    Last edited: Aug 19, 2015
  8. Doug J.

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    John, I think one way to get rid of the jitter is to slow down your panning. Since your videos display more jitter and not the jello effect, you might have to increase the shutter speed if possible. Though it looks like you might already be maxed out at with the available light.
     
  9. John Lo

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    Doug J., thanks for ur advise. and I mixed up with jello and jitters issue, Jello effect, as we all know, it is very common for all cmos sensor and i understand that. To reduce the effect by using your suggestion.

    what I really concern is the actual frame rate for PAL video. If P3 can record video in NTSC mode only, drop frame to suit PAL mode, there will be a big mistake , create a lot of jitters and you watch the video very uncomfortable. I need P3 native support PAL video record, not NTSC mode with drop frame.

    This problem can be reduced, but can't be solved completely by panning the P3 slowly or go higher sutter speed. It is because the drop frame process is doing after capturing the video by sensor.

    I hv send the issue to DJI America by email, hope they will address it and fix it on next firmware update if possible.
     
    #9 John Lo, Aug 19, 2015
    Last edited: Aug 19, 2015
  10. 4wd

    4wd

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    PAL and NTSC are increasingly irrelevant except they allow different frame rates.
    If you have a reasonably modern TV it will play either.
    If you mainly upload material online it doesn't make any difference at all except any processing should be aware of the frame rate used when recording.