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  1. #21

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    David, with all due respect... the solenoid has nothing to do with flash firing current. One does not connect a flash to the solenoid. The solenoid trips the shutter and provides a mechanism for controlling the delay required for flash bulb use. The benefit is to trip the shutter and flash "simultaneously" using the red button on a Graflite flash handle.

  2. #22
    David H. Bebbington's Avatar
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    Quote Originally Posted by BrianShaw View Post
    David, with all due respect... the solenoid has nothing to do with flash firing current. One does not connect a flash to the solenoid. The solenoid trips the shutter and provides a mechanism for controlling the delay required for flash bulb use. The benefit is to trip the shutter and flash "simultaneously" using the red button on a Graflite flash handle.
    Brian, my "office ornament" is a side-rangefinder Pacemaker Crown Graphic with a 3-cell Graflex flashgun. I freely admit I've never fired it, but the flashgun has 5 pairs of sockets, each of which takes a US household-style plug. These are labeled "Extension", "Shutter", "Battery", "Remote" and "Solenoid". Cables were (in fact still are) available with a household plug on one end and a bipost male, bipost female, household or 3 mm PC connector on the other. The solenoid on the lens panel has a hook on the end of its plunger which wraps around the firing lever of the shutter, while at the bottom of the solenoid is a female bipost socket. I assume that connecting from "Solenoid" on the flashgun to the base of the solenoid will cause this to fire the shutter when the red button at the rear of the flashgun is pressed. I also assume another alternative would be to use the body release on the camera, which pushes down on the shutter firing lever, and hook up the flash from the "Shutter" socket on the flashgun to the bipost terminals on the shutter. My conclusion is that the solenoid essentially provides a means of synchronising a non-synchronised leaf shutter and therefore became redundant when synchronised shutters became available, except that. as I said, you could potentially be using a very heavy firing current with dozens of bulbs and the solenoid would isolate the shutter from this.

    Regards,

    David

  3. #23
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    Quote Originally Posted by David H. Bebbington View Post
    My conclusion is that the solenoid essentially provides a means of synchronising a non-synchronised leaf shutter
    Yes. this is correct.

    Quote Originally Posted by David H. Bebbington View Post
    except that, as I said, you could potentially be using a very heavy firing current with dozens of bulbs and the solenoid would isolate the shutter from this.
    This gave me pause...but I think I understand what you're saying. The problem is you come to the point so quickly that at first it seems incorrect. It is largely a matter of point of view. Let us assume that you have a large number of flash bulbs to fire and that this would require a large current (I'm not entirely convinced of this but, let us assume it is the case for now).

    I think what you're saying is that one could try to connect all of these to the flash synch terminals on the shutter itself and that, due to the large current involved, this might be a problem to be avoided.

    In this case one could trigger both the shutter solenoid and the flash bulbs with some external switch and in this manner "isolate" the flash current from the shutter...correct? I think "isolate" is the wrong word here but, that is a nit. A transistor connected to the shutter's flash synch switch would isolate the shutter from the flash current. The solenoid is just completely avoiding the shutter's flash synch switch altogether.

  4. #24
    Colin Corneau's Avatar
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    I can vouch for using the Crown Graphic as a field camera. My old Crown didn't have a rangefinder, so I got into 4x5 focusing on the GG - it was a good habit to get into as I moved up to a Shen Hao field cam. You likely won't be using it for candids or street photography, etc. anyway.

    I also used regular Fidelity-type film holders, which also work nicely with other field cams...Crowns or Speeds are a great way to get into LF photography.

  5. #25
    David H. Bebbington's Avatar
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    Quote Originally Posted by BradS View Post
    Yes. this is correct.



    This gave me pause...but I think I understand what you're saying. The problem is you come to the point so quickly that at first it seems incorrect. It is largely a matter of point of view. Let us assume that you have a large number of flash bulbs to fire and that this would require a large current (I'm not entirely convinced of this but, let us assume it is the case for now).

    I think what you're saying is that one could try to connect all of these to the flash synch terminals on the shutter itself and that, due to the large current involved, this might be a problem to be avoided.

    In this case one could trigger both the shutter solenoid and the flash bulbs with some external switch and in this manner "isolate" the flash current from the shutter...correct? I think "isolate" is the wrong word here but, that is a nit. A transistor connected to the shutter's flash synch switch would isolate the shutter from the flash current. The solenoid is just completely avoiding the shutter's flash synch switch altogether.
    This may turn into "More than anyone ever wanted to know about Graflex flashguns" but as far as I can see the red button on the flashgun, the bottom of the solenoid, the flashbulb, any extension flashguns and any extension power pack (which could be, and often was, a 90V radio battery) are all in the same circuit. This is what I meant when I said the solenoid isolates the camera shutter from a heavy current. In fact you are right - a solenoid usually acts as an isolator by having a small energising current on one side and a heavy switching current on the other which are not electrically connected (and are therefore isolated). In the case of the Graphic solenoid, it of course has a current only on one side, the other side is not electrical at all but is a mechanical link to the shutter. Someday I must got out and try to take some shots like O. Winston Link and put all these ideas to a practical test!

    Regards,

    David

  6. #26

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    I wouldn't pass on a graphic due to it having a lens other than a Schneider. Best to get a good, working body with a working lens. Later on, if you decide that you love LF and want to plunk some money, you can certainly upgrade to a nice Schneider, Rodenstock, Nikon, Fujinon, etc.

    If you don't mind a bit of extra weight, you could go the Speed Graphic route and use barrel lenses which are much less expensive than lenses in shutters. Goerz dagors, artars, aero ektars and petzvals, all sorts of lenses. And if you get a speed with side-mounted kalart rangefinder you can calibrate it to any one particular lens at a time.

  7. #27
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    Quote Originally Posted by k_jupiter View Post
    Have the electronics checked very carefully. Electronic repair people for a Crown Graphic are in short supply.

    tim in san jose
    depends on age. my 1947 CG has no electronics.

  8. #28

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    My first speeder came with a 162mm Wollensak Velostigmat, which turned out to be a beautiful lens, especially for portraits. A Crown showed up at my door one day with a 127mm Ektar (uncoated) and it is an extremely sharp lens. Hardly any room for movements, but there aren't hardly any on a crown anyway. I'm currently playing with a 203mm ektar and it is a very sweet lens--- sort of like a baby artar.
    Both the Wolly and the 203mm pull double duty on other cameras which do allow for movements.
    My point being that there are plenty of great lenses you'll find riding aboard graphics that aren't schnieders.
    Happy graphic hunting!

  9. #29

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    Quote Originally Posted by BrianPhotog View Post
    depends on age. my 1947 CG has no electronics.
    If you are a portrait photographer, please be watchful for your model's tongue in cheek. Or... read the whole thread.

    tim in san jose
    Where ever you are, there you be.

  10. #30

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    Quote Originally Posted by John Kasaian View Post
    My point being that there are plenty of great lenses you'll find riding aboard graphics that aren't schnieders.
    Happy graphic hunting!
    My Speed takes great pictures with a 150 6.3 Fuji lens.

    It's a light tight (hopefully) box.


    tim in san jose
    Where ever you are, there you be.

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