Darn Bulb .. quick emergency question! Omega Dichroic

Discussion in 'Darkroom Equipment' started by 5stringdeath, Jul 18, 2010.

  1. 5stringdeath

    5stringdeath Member

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    My bulb went last night in my D5 head ... and I thougth I had a spare around, but apparently I don't. As I really wanted to finish some printing tonight and not waste the chemistry, can someone tell me if I can do this .....

    So its supposed to use a 250w 24v bulb .. Omega part 471-029

    All I have on hand is a:

    250w 82v bulb

    I realize I may deal with having to adjust my exposure times, but I can deal with that. Just wondering if this will blow anything up :smile: I'm using a Chromegatrol, which as I understand it, puts out a constant voltage ... so in my mind the bulb won't put out its full 250w ...

    TIA!
     
  2. epatsellis

    epatsellis Member

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    Nope, won't work. an 82v bulb run on 24v might glow, a little, but that's about it. Doesn't Croeve Couer camera stock them? (or may OJ's if he's still open)


    ...Thinking about it, I need to get a spare for my Dichro head. Thanks for reminding me!!!!
     
  3. wclark5179

    wclark5179 Member

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  4. 5stringdeath

    5stringdeath Member

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  5. wclark5179

    wclark5179 Member

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    missed that in your original post!

    Sense your frustration. Bummer.

    You could have them Fed X overnight tomorrow, probably cost more than the bulb!

    Order 2!

    Do you have the condenser head?
     
  6. epatsellis

    epatsellis Member

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    Is Schiller's open today, I'm pretty sure they would have a bulb as well.
     
  7. fschifano

    fschifano Member

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    This place has the cheapest and best selection of ELC lamps. I use them.

    http://www.topbulb.com/find/Product_Description.asp?intProductID=43908.

    'Course this doesn't solve your immediate problem, but you might want to consider stocking up on a few. Teh ones I've pointed you to have a 500 hour lifespan as opposed to the more usual 50 hour life, and they work just fine in your head. I know. I use them. You can get the 50 hour life lamps for less at the same place, but these are a better deal over the long run.
     
  8. AgX

    AgX Member

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    82V, isn't that a kind of weird voltage? Never heard of that.
     
  9. David Brown

    David Brown Subscriber

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  10. fschifano

    fschifano Member

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    The lamp he needs is definitely the ELC 250 watt, 24 volt model. I have the same head for my D4. That's the one. The 82 volt lamp is for something else and will not work in this head.
     
  11. Anscojohn

    Anscojohn Subscriber

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    **********************
    It is an unwritten darkroom law that anything untoward that shall happen shall always be on Sunday night when the photographer has a Monday deadline.
     
  12. 5stringdeath

    5stringdeath Member

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    Schiller's is closed on Sundays :rolleyes:
     
  13. Sirius Glass

    Sirius Glass Subscriber

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    FreeStyle. The website is always open.
     
  14. 5stringdeath

    5stringdeath Member

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    Yes but Schillers is .5 miles from my house :D
     
  15. eddie

    eddie Subscriber

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    At least in the old days, you could hit up a friend to get you through. I can't remember how many times I borrowed, or gave, a gallon of Dektol, D76, etc. on a Sunday night...
     
  16. 5stringdeath

    5stringdeath Member

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  17. ic-racer

    ic-racer Member

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    The Omega heads with a pulse width modulated regulated/stabilized voltage use 82V bulbs. Many Omega heads that are unreguulated or that use the ferroresonant transformer for regulation, use 24V.
     
    Last edited by a moderator: Jul 19, 2010
  18. Steve Smith

    Steve Smith Member

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    Take 110 volts ac (US standard supply) and connect it to an 82 volt bulb with a diode in series. The half wave rectification effectively converts the RMS voltage of the supply to about 82 volts.

    No idea why they do this though when they could use a 110 volt bulb and not bother with the diode.


    Steve.
     
  19. AgX

    AgX Member

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    Many thanks, Steve.