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  1. #1

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    LED bulbs for safelights

    I'm looking to get some LED bulbs to use as safelights for making film speed emulsions. (I use Doran sleeves on fluorescents bulbs for regular darkroom work.)

    I currently have 2 Westinghouse 1 watt Nanolux bulbs. $10 or so. http://www.amazon.com/Westinghouse-N.../dp/B000UQ1Y0Y

    This bulb works really nicely at about 3 ft from my work area when in a conical reading lamp housing, but I'd like something a little more powerful to cover more area. Westinghouse also makes a 3 watt version that I was thinking of trying, but I thought I'd see if anyone here has actually tried some LED bulbs.

    So, what have you tried and what did you think?

  2. #2

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    I make my own - at the moment I'm using 3 10mm LEDs, although I'm going to add more because I too could do with some more light.

    If you're handy with a soldering iron it really isn't very hard...

  3. #3

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    I'm using an OptiLED bulb mounted in the regular ceiling fitting. It is very bright but doesn't fog the paper. Unfortunately it is so bright that it is difficult to focus the enlarger because I can barely see the image on the baseboard.

  4. #4
    Lee L's Avatar
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    Search APUG for "led safelight" and you'll come up with multiple threads with many individual suggestions for suppliers and set ups.

    Lee

  5. #5

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    Does anyone know if any of those LED bulbs come with ORANGE COLOR with peak spectrum at around 625nm?

  6. #6
    Anscojohn's Avatar
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    Quote Originally Posted by paul ewins View Post
    I'm using an OptiLED bulb mounted in the regular ceiling fitting. It is very bright but doesn't fog the paper. Unfortunately it is so bright that it is difficult to focus the enlarger because I can barely see the image on the baseboard.
    Paul, What color is your Optiled?

    John, Mount Vernon, Virginia USA

  7. #7
    Jon King's Avatar
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    I use a 1W Luxeon Red LED, although Ryuji, it is spec'd with a dominant wavelength of 625nm. I rolled my own, powering it with a wall transformer through a resistor - it isn't an accurate currant source, but good enough for the application.

    I'm bouncing it off the ceiling of a 11x12 foot room, and it is bright enough to see well. It is bright enough I need to block it when using an EM-10 exposure meter. People coming into the room don't need much time for their eyes to adjust. Ilford MG paper was good for 8 minutes without fogging - I got bored testing after that.:o
    Jonathan
    -----------------------------------------------

  8. #8
    Ken Nadvornick's Avatar
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    I made a simple light bar consisting of six 627nm-rated red OptiLED S-11 Festival mini-bulbs (http://www.lightworld.com/optiled/index.asp?id=5). This allows me to configure six different levels of brightness as needed.

    I then ran a safelight test using pre-flashed Ilford MGIV RC paper. I used a five-minute step resolution. The illumination level was sufficient during the test for me to read a magazine while I waited through 12 steps (60 minutes). After processing and careful examination, I could detect absolutely no fogging whatsoever. Oddly, however, the same test executed using Kentmere Bromide grade 3 showed fogging at the 20 minute mark. All tests were run with all six LEDs lit and located approximately seven inches from a 9-foot matt-white acoustical tile ceiling.

    Afterward, a cursory spectral analysis (using one of my son's CDs) did show a sliver of blue-green emissions from these bulbs. Apparently the Kentmere must be more sensitive to these residual emissions.

    Ken
    Last edited by Ken Nadvornick; 04-15-2008 at 01:52 PM. Click to view previous post history. Reason: URL link didn't take

  9. #9
    RJS
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    I am using two Optiled lights, I believe they are 625 in color - quite bright. I have them in cone shaped fixtures bounced off a fairly low ceiling. I ran tests as described in Beyond Monochrome (?) and found if bounced they are fine; aimed at Ilford MG from four feet they will fog after a couple of minutes. I process paper face down (I like to be surprised) and the safelight by my enlarger is switched off when the enlarger goes on so exposure to the safelight is brief.

  10. #10

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    Quote Originally Posted by Ken Nadvornick View Post
    Apparently the Kentmere must be more sensitive to these residual emissions.
    Kentmere papers are quite fast.

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