Flash unit

Discussion in 'Digital Discussion & Q&A' started by larrytcom, Aug 17, 2007.

  1. larrytcom

    larrytcom TPF Noob!

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    I am new to this forum, but Im sure I can get the answers to all my questions here. I am trying to take a picture of a hummingbird and stop the wing with clerity in the photo. I just dont have the setting right Im sure. My question is, if I set my shutter speed at lets say 1250 and my ISO at 400, will adding a flash unit help achieve what I want. I am using a tripod, and a shutter cable, and a 24 - 70mm f/2. 8 lens. Please feel free to correct what ever Im doing wrong.
     
  2. Big Mike

    Big Mike I am Big, I am Mike Staff Member Supporting Member

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    There is a problem with your theory. Most modern SLR cameras use a focal plane shutter...which will limit the shutter speed that you can use with flash. Each of these cameras has a max sync speed, which is the fastest that you can reliably use flash. It's probably around 1/200, give or take.

    Now, the burst of flash is very fast...maybe 1/10,000. That should be fast enough to freeze the wings...but the problem is that you still have the ambient exposure, which might still blur the image over the sharp 'flashed' image. The darker it is, the better for getting a sharp flash shot.

    The other alternative would be to get as much ambient or continuous light as possible, use a high ISO and get as fast a shutter speed as you can.
     
  3. Jon, The Elder

    Jon, The Elder TPF Noob!

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    Especially Hummingbirds. A true strobe is the only sure way and that is going to require a triggering setup.
     
  4. Garbz

    Garbz No longer a newbie, moving up!

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    Except the strobe will limit your shutter speed again. 1/4000th or 1/8000th is enough to freeze the wing I think. This should easily be doable with a fast lens in the sun.

    As for flashing the only way it can work is to make the scene as DARK as possible. Something like max sync speed 1/250th, at f/22 ISO100 and blast it with a very powerful flash so the only light that is recorded comes from the short burst of a flash.

    The problem again is a standard SB-800 unit at full power runs for 1/1050th of a second which is too long to freeze the wing, and at 1/8 power I doubt you generate enough light to over power mother nature. Unless you can photograph the birds at night...
     

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