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  1. #11
    Edimilson's Avatar
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    I wonder if it has to do with the different color temperatures involved. Household lamps aren't as white as the special lamps used in enlagers, isn't that so?

  2. #12
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    Quote Originally Posted by Edimilson View Post
    I wonder if it has to do with the different color temperatures involved. Household lamps aren't as white as the special lamps used in enlagers, isn't that so?
    I think you are correct in the temp diff. Household bulbs are more yellow, less blue, cooler. Something like 2400K-3200K vs 4800K ??? Don't quote me on that, but it seems like I had read that somewhere before. But I filter a "lot", so it was a matter of finding correct compensation.

  3. #13
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    If it could be of interest to anyone, we have a stock of about 80 or so original Philips 75W 220V enlarger bulbs (PF603E/51) for condensor-type enlargers. A few are on Ebay (item no. 170080610501).
    Last edited by foto-r3; 06-10-2007 at 07:54 AM. Click to view previous post history.

  4. #14
    AgX
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    Quote Originally Posted by Freneticist View Post
    Household bulbs are more yellow, less blue, cooler. Something like 2400K-3200K vs 4800K ??? Don't quote me on that, but it seems like I had read that somewhere before.
    The maximum what is normally gained from an incandescent lamp is 3400°K for long time use, with halogen lamps. Those old photoflood lamps were plain incandescent lamps intended to be run overrated which gained 3200-3400°K depending on type, but they only run a few hours. Actually I don't know whether those enlarger lamps were overrated too.
    Anyway, a light colour of 4800°K could with incandescent lamps reasonably only be achieved via employing a colour filter on the glass bulb.

    (As here in Europe the net voltage has been lifted up over the last years, there is another overrating issue with old lamps.)

  5. #15
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    Using household bulbs may not be a long term solution in the European Union countries because manufacture has to be phased out to allow for replacement by low-energy bulbs. These all seem to have flourescent tubes and are often larger than standard bulbs, so whether they could be used in enlargers I don't know.

  6. #16

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    Quote Originally Posted by Daniel_OB View Post
    I quit all special bulbs and batteries. My Beseler is now happy with $0.5 house bulb, instead of $20 "special" bulb. Just a little work around and all is fine. So better investigate some solution than let manufacturer to investigate how to take your money.

    www.Leica-R.com
    Daniel_OB - what was the workaround needed to utilize the $0.50 house bubl?

  7. #17

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    What about an LED light source, anyone figured out how to place one in a Durst 138S condenser enlarger. I can't see how a compact flourescent bulb would work considering it takes a minute for it to warm up to full brightness.

    LED's have no mercury, would most likely last a lifetime and barely give off any heat. I imagine the price would be at least as much as a lifetimes worth of incadescent enlarger bulbs.

  8. #18

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    Quote Originally Posted by radiantdarkroom View Post
    What about an LED light source, anyone figured out how to place one in a Durst 138S condenser enlarger.
    One potential problem with LEDs is their spectral response. "White" LEDs aren't really white. I don't know how they'd respond to filtration. You might do better with a combination of blue and green LEDs (and red, if you want to do color enlargements).

    Another problem with LEDs is their brightness. Just for the heck of it, I tried replacing the halogen bulbs in my Philips PCS150 with LEDs. The results, even when I used colored bulbs, was a light source that was so dim I didn't even bother testing it to see how much of a drop in light there had been.

    That said, it's possible that future developments in LED technology will make them a more suitable drop-in replacement for tungsten or halogen bulbs. If there's lots of space in your enlarger where your bulb goes, perhaps you could find some truly enormous LED replacement bulb that would be worth trying; and if it doesn't work, use it for normal room lighting. It's also conceivable that custom-designed LED arrays could be created for enlargers. In fact, there's at least one person who's doing this.

  9. #19
    Cor
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    i do remember somebody else working this concept, from the time when Usenet was still very active...so you might check with the author if his project is still alive..see : http://www.trailing-edge.com/~shoppa/led.html

    (his web side does not seem updated)

    Best,

    Cor




    Quote Originally Posted by srs5694 View Post
    One potential problem with LEDs is their spectral response. "White" LEDs aren't really white. I don't know how they'd respond to filtration. You might do better with a combination of blue and green LEDs (and red, if you want to do color enlargements).

    Another problem with LEDs is their brightness. Just for the heck of it, I tried replacing the halogen bulbs in my Philips PCS150 with LEDs. The results, even when I used colored bulbs, was a light source that was so dim I didn't even bother testing it to see how much of a drop in light there had been.

    That said, it's possible that future developments in LED technology will make them a more suitable drop-in replacement for tungsten or halogen bulbs. If there's lots of space in your enlarger where your bulb goes, perhaps you could find some truly enormous LED replacement bulb that would be worth trying; and if it doesn't work, use it for normal room lighting. It's also conceivable that custom-designed LED arrays could be created for enlargers. In fact, there's at least one person who's doing this.

  10. #20

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    DeVere is selling an LED light source for their Digital enlarger line. It's looks like it's only half as bright as a Halogen light source. I'm sure it could be used for film.

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