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  1. #21

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    I asked on the sci.engr.lighting newsgroup and the claim was that the bulbs are rated for 25C. The basement is lucky to hit 20C. I'm going to use two 12v fans. One pushing in air one pulling it out. Yesterday I found out somebody opened up a surplus store nearby. No more 40 minute drives just to wander around and look at junk They have a 12v lead acid rechargable on sale this week for $12 that I'll use for the fans. Over kill but I already have the charger.

    Right now I'm thinking one of those 105watt bulbs should be enough. No? I might go for two. The intended size for the head is 12"x12"x18". With the head being at least 12"x12" I'm hoping the light will be even enough in the centre 8x10 area.

  2. #22

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    Quote Originally Posted by Nick Zentena
    I asked on the sci.engr.lighting newsgroup and the claim was that the bulbs are rated for 25C. The basement is lucky to hit 20C. I'm going to use two 12v fans. One pushing in air one pulling it out. Yesterday I found out somebody opened up a surplus store nearby. No more 40 minute drives just to wander around and look at junk They have a 12v lead acid rechargable on sale this week for $12 that I'll use for the fans. Over kill but I already have the charger.

    Right now I'm thinking one of those 105watt bulbs should be enough. No? I might go for two. The intended size for the head is 12"x12"x18". With the head being at least 12"x12" I'm hoping the light will be even enough in the centre 8x10 area.

    I have a 250 watt lamp in my Durst 138S which is a condensor enlarger. Due to the fact that it is a condensor enlarger it does not suffer from the light loss that diffusion material would cause. It is interesting that Durst Pro USA now offers a lamp upgrade for my enlarger that involves a 1200 watt lamp. Both of these involve far more light then you are wanting to use. My exposures can become lengthy with dense negatives using the lamp that I now use.

    I really think that considering the coverage that you are wanting to achieve that two very distinct potential problems exist. The first is the amount of light that you are wanting to use and the second is the matter of even light output over the negative area. Thus I would say that your concern about heat output may very well be the least of your concerns.

    However, it is when people learn to think outside the box of conventional practice that oftentimes new methods are discovered. There is also the concept of one being "penny wise and pound foolish".

  3. #23

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    Donald that 250 watt bulb isn't a fluorescent is it? I'm also guessing the Durst is capable of making bigger enlargements. I'm building everything so it'll be big enough for 3x from 8x10 but the goal is 2x. I could easily add more then one bulb to the head. All it'll take is drilling a hole for each bulb.

    About two weeks ago I did a test. Old 4x5 monorail. 19 watt fluorescent flood light. The projected image was quite bright. I didn't try to make a print but did take an incident meter reading. It was better then I expected. The 105 watt bulb is allegedly equal to a 500 watt incandescent. I'm also counting on the 5000k bulb being a better match to photo paper then a 2700K bulb would be.

  4. #24

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    Hi there,

    Nick, try the link

    http://scientificsonline.com/product.asp_Q_pn_E_3082488 --

    It's to something called 'Live Wire', comes in blue, green and magenta. Could be an instant color cold lamp for you or anyone.

    Good luck with it.

  5. #25
    Donald Qualls's Avatar
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    Quote Originally Posted by phfitz

    http://scientificsonline.com/product.asp_Q_pn_E_3082488 --

    It's to something called 'Live Wire', comes in blue, green and magenta. Could be an instant color cold lamp for you or anyone.
    Did you read that page? Those things (stripwise electroluminescent panels, I think) cost $75 and run off a 9V battery -- which means they can't output as much light as a pocket flashlight. Similar units in useful power levels would be very welcome, but at that pricing, it would cost much more to build an enlarger light source with them than it would to simply buy a color head with high power hot light -- and then install a cooling system for it to keep your darkroom comfy!
    Photography has always fascinated me -- as a child, simply for the magic of capturing an image onto glossy paper with a little box, but as an adult because of the unique juxtaposition of science and art -- the physics of optics, the mechanics of the camera, the chemistry of film and developer, alongside the art in seeing, composing, exposing, processing and printing.

  6. #26

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    Hi there,

    "Did you read that page?"

    Yes, I did. Did you? They are 25 feet long, how many coils in a concentric is that? Blue and green for split printing, perfectly even illumination, no heat, no vibration= really hard to live with. No heat means you can use a double ground glass diffuser panel for zero light loss instead of a heat absorbing glass and mixing chamber with 2 opal or acrylic diffusers which cut the light to 1/4.

    "Those things (stripwise electroluminescent panels, I think) cost $75 and run off a 9V battery -- which means they can't output as much light as a pocket flashlight."

    Not being funny, but welcome to the 21th century. Have you even seen an L.E.D. flashlight? Bright enough to hurt. It also runs from an A.C. converter. Low voltage = no safety problems. Packard shutter = no timing circuits. I was actually thinking of using the same for a 5X7 enlarger. Just think, you could actually take it on the road if you wanted to, just use a reducer from 12 volt.

  7. #27

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    I'll have to side with Mr. Qualls. I've two LED lights; one on a
    headband and used in the deep dark forest as a nifty night light.
    The other is more multi-purpose though very good
    outdoors at night as well.

    BIG plus with these LEDs is the fair light output along with
    nearly unbelieveable battery life span. Dan

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