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How much is your lag? (easy to measure)

Discussion in 'Pro/Adv Discussion' started by 43k, Aug 5, 2015.

  1. 43k

    43k

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    So, it would be interesting to see how much lag different tablet models generate, or even the variation for users with the same tablet model.


    How to measure:

    1. I suggest to set the video mode to NTSC to get the 60 fps capability, and then set the video format to 720p, 60fps (tap "Fn" above the record button to set this)

    2. Place the tablet in front of the copter/camera so that you can see the tablet in the video (does not matter if out of focus and blurry)

    3. Start recording and just move some object in front of the camera a couple of times

    4. Open the recorded video in some video editing software and count the number of frames of the delay/lag
      I.e. the number of frames it takes for the object to appear at the same spot in the first generation, compared to the second generation.
    This is what it might look like:
    [​IMG]


    I counted to 13 frames @ 60 fps = 1/60 x 13 = 217 ms

    My setup:
    P3P, fw:1.3.20
    Tablet: Nexus 7 II, android 5.1.1
     
  2. witold

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    I only used a stopwatch and later compared in the video. It's about 0.3 seconds for me.

    Lag is not the main problem though. It's stuttering video. I'm using galaxy tab pro. The video stutter is what makes it painful to fly.
     
  3. 43k

    43k

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    For me, lag is really annoying while shooting video and trying to do smooth pans and tilts.

    Edit:
    I have not seen any stutter so far with the Nexus 7 II.
    I would definitely have noticed.

    Maybe it is that the Spamsung tablets have all this bloatware loaded?

    I will give it a go with my Samsung Galaxy Note 12 and see what the result is.
    How long is it before you see the stuttering after a power on?
     
    #3 43k, Aug 5, 2015
    Last edited: Aug 5, 2015
  4. Miguel Silva

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    Ipad Mini2
    P3A Fw 1.3.2

    11 Frames @ 50fps = 1/50*11 = 220ms
     
  5. 43k

    43k

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    I tried it with the Samsung Galaxy Note 12 (way to big for this o_O) and got about the same lag, 12-13 frames @ 60 fps = about 200 ms

    But I did not run it for long. Maybe the stuttering starts after running for a while?