Darn Bulb .. quick emergency question! Omega Dichroic

5stringdeath

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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 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!
 

epatsellis

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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!!!!
 

wclark5179

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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?
 

epatsellis

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

fschifano

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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.
 

AgX

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

fschifano

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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.
 

Anscojohn

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5stringdeath said:
Yes I know where to order them but wanted to finish today

Ah well I'll finish next weekend. Thanks all.
Click to expand...

**********************
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.
 

eddie

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Anscojohn said:
**********************
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.
Click to expand...

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...
 

ic-racer

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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.
 
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Steve Smith

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AgX said:
82V, isn't that a kind of weird voltage? Never heard of that.
Click to expand...

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.
 
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