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Thread: Open Bulb Flash technique questions

  1. #1

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    Open Bulb Flash technique questions

    As I understand it open bulb flash means one opens the shutter on bulb, time or for as long as we want in a dark photography arena.

    Thus the shutter is open and we trigger the flash manually at that time.

    This can be flashbulbs, studio flash, Speedlights or lightning I suppose.

    The reason I bring this up, is I just got what appears to me, an open bulb flashbulb holder. It has no wired or wireless connection. It's labelled REXO Burke & James, and is nicely made of aluminum. It seems to hold 2 C batteries, but I would think in it's era a higher voltage battery would be used.
    In the pics, it has a medium base flash bulb the size of a common light bulb mounted. No batteries yet. It has a small test bulb on top, which as I write this must be only a normal flashlight bulb of 3 to 5 volts.

    The reflector is 11" in diameter. I could not resist, it was $15...

    Does anybody know anything about this? Have you used one?

    I will get batteries next week at Costco.

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  2. #2

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    Re: Open Bulb Flash technique questions

    Don't know that flash but the little dome on the top could be a sensor to use it as a remote?

  3. #3

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    Re: Open Bulb Flash technique questions

    Quote Originally Posted by mdarnton View Post
    Don't know that flash but the little dome on the top could be a sensor to use it as a remote?
    Maybe, but this thing seems simpler than that. I tried optical slave trigger the other day and no go with a different rig.

    I need batteries to test it. And I will wait for the buy a dozen deal at Costco.

  4. #4
    Jim Jones's Avatar
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    Re: Open Bulb Flash technique questions

    Two 1.5 Volt batteries are sufficient to ignite a flash bulb. Many flashes back then used two or three batteries as small as AA size.

  5. #5
    Jac@stafford.net's Avatar
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    Re: Open Bulb Flash technique questions

    Does anybody know anything about this? Have you used one?
    Yup. The very big reflectors were not popular largely because they interfered with the photographer's head, as you can imagine.

    I have one particularly thorough volume on bulb flash photography published in the 40's I wish I could copy it for you.

    Google Books, perhaps? I will look into this!

    Jim Jones: Two 1.5 Volt batteries are sufficient to ignite a flash bulb. Many flashes back then used two or three batteries as small as AA size.
    True. And no surprise that around WWII we could get big bulb flashes that used NO batteries at all, largely made in the USA and Britain. I've posted pictures of some.

    Here is an unusual, possibly rare version bracketed for a Leica. I have one! I have a couple more different universal versions I could post as well.

    .

  6. #6

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    Re: Open Bulb Flash technique questions

    Quote Originally Posted by Jac@stafford.net View Post
    Yup. The very big reflectors were not popular largely because they interfered with the photographer's head, as you can imagine.

    I have one particularly thorough volume on bulb flash photography published in the 40's I wish I could copy it for you.

    Google Books, perhaps? I will look into this!



    True. And no surprise that around WWII we could get big bulb flashes that used NO batteries at all, largely made in the USA and Britain. I've posted pictures of some.

    Here is an unusual, possibly rare version bracketed for a Leica. I have one! I have a couple more different universal versions I could post as well.

    .
    Magneto I suppose. Costly initially but would work for a long time.

  7. #7
    Jim Jones's Avatar
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    Re: Open Bulb Flash technique questions

    Quote Originally Posted by Randy Moe View Post
    Magneto I suppose. Costly initially but would work for a long time.
    More likely mechanically ignited. A sharp blow on some crystals produces a spark.

  8. #8
    Jac@stafford.net's Avatar
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    Re: Open Bulb Flash technique questions

    Quote Originally Posted by Randy Moe View Post
    Magneto I suppose. Costly initially but would work for a long time.
    Exactly, a magneto ignites the bulb. The front button releases the spring driven rotor which has a cam inside which pushes the shutter or cable release. It can use Graflex reflectors and electrical extensions.

    Here is a diagram of a typical unit
    , including the bulb adapter for edison/mazda bulb to smaller ones.

    The cam has an adjustable delay.

  9. #9

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    Re: Open Bulb Flash technique questions

    The higher the current, the sooner the bulb fires. For synchronized flash, milliseconds count and the BC (battery-capacitor) flashes of the 1950s and '60s were a way to get amperes of current from a battery small enough to fit into one of the collapsible-reflector shoe-mount units for 35mm cameras. Obviously, a bit of delay in igniting an open-flash bulb is not critical, and the actual current needed is not all that much if one can wait for the igniter to heat up. The higher the current, the sooner the bulb fires.

    One of the product warnings for the medium-base bulbs was to always handle them with gloves---static electricity can fire one, and the combination of heat and ultraviolet light will give you a pretty badly burned hand. When I was about nine, I found some of these bulbs, and fired one with a car battery...while holding the bulb in my left hand. Not gonna make that mistake ever again!

  10. #10

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    Re: Open Bulb Flash technique questions

    Quote Originally Posted by Harold_4074 View Post
    The higher the current, the sooner the bulb fires. For synchronized flash, milliseconds count and the BC (battery-capacitor) flashes of the 1950s and '60s were a way to get amperes of current from a battery small enough to fit into one of the collapsible-reflector shoe-mount units for 35mm cameras. Obviously, a bit of delay in igniting an open-flash bulb is not critical, and the actual current needed is not all that much if one can wait for the igniter to heat up. The higher the current, the sooner the bulb fires.

    One of the product warnings for the medium-base bulbs was to always handle them with gloves---static electricity can fire one, and the combination of heat and ultraviolet light will give you a pretty badly burned hand. When I was about nine, I found some of these bulbs, and fired one with a car battery...while holding the bulb in my left hand. Not gonna make that mistake ever again!
    Now that you say that, I think that was a favorite stunt to pull on the unsuspecting.

    I now remember somebody showed me a wire, a flash bulb and a car battery, and sure enough the joke was on me. The cruel 50's as I call them.

    Now I have found a use for that stupid windup flashlight my employer once gave me as reward for being a fool.

    It's a generator with a capacitor and a battery and will be good for popping flashbulbs!

    If I can only find it...

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