A&P Halp - flash set up

Discussion in 'Lifestyle' started by aCab, Sep 4, 2008.

  1. aCab

    aCab New Member

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    Alright,

    i just bought 2 580ex's and a 430ex from Devin. I had a 550ex before.

    I'm going to sell what, but what do I sell? The 550 or the 430? I'm keeping both 580's.
     
  2. NOR*CAL

    NOR*CAL OT Supporter

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    It's nice to carry a compact flash when you can.
     
  3. mojito

    mojito New Member

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    test both, which ever is more powerful, keep that one.
     
  4. aCab

    aCab New Member

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    550 is more powerful, i dont even have to test them.
     
  5. mojito

    mojito New Member

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    :nono:

    EVERY flash is different, don't go by posted GN alone. they're usually all very underpowered compared to tech specs :squint:
     
  6. Killyin

    Killyin Vicariously I, live while the whole world dies.

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    For serious? ....

    I figured that they were all built to meet or exceed the GN. I didn't think they would actually fail to make the spec.
     
  7. mojito

    mojito New Member

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    :sadwavey:

    its easy to test if you have a light meter. if not, take a gray card, or at the least, a white piece of paper.

    measure of 10'

    place your flash on a stand there

    set it to M, 1:1


    set the camera to anything under the sync speed for shutter speed

    iso can be anything, but might as well start at 100

    Adjust aperture till you get a perfectly exposed image

    Note the Ap, times it by 10, thats your GN at iso 100. The guide number then moves along the ap scale as you move your ISO. So if your iso 100 ap was 5.6, that means its a GN of 56 at iso 100, or GN 80 at iso 200, GN 110 at iso 400 etc


    also on cheaper flashes, they will list teh GN at higher iso to make it look more powerful :mamoru:
     
    Last edited: Sep 5, 2008
  8. Killyin

    Killyin Vicariously I, live while the whole world dies.

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    Those bastards :mad:
     

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