240fps slow motion video doesn't work right under florescent lights

Discussion in 'iPhone' started by JoeTomasone, Sep 19, 2014.

  1. JoeTomasone macrumors 6502

    Joined:
    Aug 8, 2014
    #1
    Very pronounced flicker that doesn't show up at 120fps. Use 120fps if you are shooting under those lighting conditions.
     
  2. HiRez macrumors 603

    HiRez

    Joined:
    Jan 6, 2004
    Location:
    Western US
    #2
    Well, it does work "right" technically, because fluorescent lights pulse at fewer than 240 fps, it's just that you never saw it before. Good thing to be aware of though.
     
  3. Taco1933 macrumors 6502

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    Aug 14, 2014
    #3
    What he said. That's just the way the lights work. Too fast for our eyes to perceive.
     
  4. XboxMySocks macrumors 68020

    XboxMySocks

    Joined:
    Oct 25, 2009
    #4
    Hahaha. It works perfectly, because fluorescent lights turn on and off at 120Hz usually - its actually recording the lights faster than your eyes can notice! :)
     
  5. Mike85 macrumors newbie

    Joined:
    Sep 20, 2014
    #5
    Thanks

    Thanks guys for this. I was working in the office here on a Saturday (loser) and I went to slow mo and panicked. Called Apple and while I was on hold found this webpage.

    Seems like the office lights are wrecking the slow mo effect lol. I'll check again when I'm home, but just wanted to say thanks :)
     
  6. JoeTomasone thread starter macrumors 6502

    Joined:
    Aug 8, 2014
    #6
    Mike,

    I tried a 240fps outside and it works fine. Like the folks here said, it's due to the nature of the lights and our perception of them. I wanted to make people aware so that they didn't panic, and I'm glad that it worked in your case. :)
     
  7. Steverd99 macrumors newbie

    Joined:
    Sep 10, 2014
    #7
    Here's my latest SLo-Mo with enough flicker to cause a SEIZURE.
    I know it's from my LED lights over the terrarium. You can even see the flicker in the original video before I slow it down from 240fps to 24fps in Adobe Premiere.

    https://www.youtube.com/watch?v=XwXN3uXovi4

    Guess I'll be using different lights to record these Poison Dart Frogs.
    Steve
     
  8. Jman13 macrumors 68000

    Joined:
    Aug 7, 2011
    Location:
    Columbus, OH
    #8
    Electric lights powered by AC will have a flicker at 60Hz. That's the cycle rate of the electricity.
     
  9. Givmeabrek macrumors 68040

    Givmeabrek

    Joined:
    Apr 20, 2009
    Location:
    NY
    #9
    It's actually 120 HZ (twice per cycle). Incandescent lights do not show this flicker effect.
     
  10. Steverd99 macrumors newbie

    Joined:
    Sep 10, 2014
    #10
    YES - BUT, look at my OTHER iPhone 6 plus Slo-Mo videos:

    (More of my Poison Dart Frogs)
    https://www.youtube.com/watch?v=kxUGUr2s3j4

    https://www.youtube.com/watch?v=uH0-54gqxrs

    Neither one was recorded under LED and neither have this kind of flicker. They where actually recorded under T-8 lighting. So since they are also "electric lights" why do they NOT record flicker?

    Thank you!
     
  11. scaredpoet macrumors 604

    scaredpoet

    Joined:
    Apr 6, 2007
    #11
    Because as mentioned earlier, these are probably incandescent lights, which work not by semiconductors emitting (and alternately not emitting) light using one phase of the alternating current (because semiconductors are typically DC-operated), but by a filament being superheated by the current, regardless of which direction it's flowing.
     
  12. kolinko macrumors newbie

    Joined:
    Dec 25, 2011
    #12

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