Anybody here make a Home Made Strobe?

Discussion in 'Lighting' started by Mark in SD, Feb 4, 2003.

  1. Mark in SD

    Mark in SD Member

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    I've always had an interest in trying some "High Speed" photography. I have Edgerton's book "Stopping Time" and, while I'm never going to be getting THAT sophisticated, I wanted to experiment a little.

    I understand the mechanics: Leave the Shutter open, and fire the flash to capture what you want, but understand from looking at some web sites that a normal fash unit fires too long a burst to be of use for this application.

    So, has anybody every tried this? How did you go about it?
     
  2. Sherman

    Sherman Member

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    How long a flash is too long? Most high power monolights have flash durations of 1/600 second or shorter on max power. Using a lower power setting results in shorter times, with some lights that can be 1/2000 second.

    If you want to photograph water drops and splashes that should work. If you want to "stop" bullets in flight or freeze exploding light bulbs I think you'll have to do a little construction.

    Sherman
     
  3. Mark in SD

    Mark in SD Member

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    Hmmm...I don't know exactly what the times are. I have a Nikon SB80 and a Nikon SB50. It looks like I'll have to do some research.

    I had always assumed that the flash times were much longer even before reading the web sites. Otherwise, why are the flash sync speeds so low? I guess I'll have to do some thinking on that and go in search of some flash specs.
     
  4. David A. Goldfarb

    David A. Goldfarb Moderator Staff Member Moderator

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    Small on-camera flashes that are manually adjustable often have very short exposure times (faster than 1/10000 sec.) and fast recycle times on low power. You could get a bunch of them and figure out a switching system to fire them in sequence.

    In general, the lower the power the shorter the time. One method for photographing dancers in motion, for instance, when you need both a small aperture to get a whole set in focus and high speed to stop action, is to use high-powered studio strobe packs with many heads on low power, so you get the full output of the pack with the shortest possible flash duration.
     
  5. David A. Goldfarb

    David A. Goldfarb Moderator Staff Member Moderator

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    Flash sync speeds are low because of the way focal plane shutters work. The X-sync speed is usually the highest speed at which the shutter opens fully. To attain higher speeds, the rear curtain begins to close before the front curtain reaches its destination. Leaf shutters will sync at any speed with a few exceptions. Modern high-speed sync focal plane shutters work by firing the flash repeatedly as the slit crosses the film gate.
     
  6. Nige

    Nige Subscriber

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