DIY Darkroom Flashlight

Discussion in 'Darkroom Equipment' started by Greg Davis, Oct 15, 2010.

  1. Greg Davis

    Greg Davis Member

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    I made a safelight flashlight from a Maglite Solitaire with an LED bulb. I bought a 3mm bulb that is in the 588nm range, similar to an OC filter, a 12v battery that is 2/3 the length of a standard AAA battery, and a resistor that measures 580 ohm and 1/2 watt. I placed the resistor in a small wooden dowel pin and inserted it all into the flash light.
     

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  2. domaz

    domaz Member

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    Very cool! Does it pass safelight fog tests? I am considering putting a couple 3W Luxeon White LEDs behind a standard safelight fixture with an Amber filter. I'm curious to see how much the Amber filter cuts down on there output and if it will put out more light than the standard 15W bulb.
     
  3. Greg Davis

    Greg Davis Member

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    This is only for making repairs on equipment in a gang darkroom without interrupting other people, so I have not checked for fogging. Since it is at 588nm, it should be fine as long as I don't get it inches from paper.
     
  4. BetterSense

    BetterSense Member

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    On the small maglights, the ones that are one step smaller than the mini-maglight (solitaire?), you can simply pull out the dual-pronged incandescent lamp and jam in the leads from a 3mm LED. The reflector fits back on and everything.
     
  5. Greg Davis

    Greg Davis Member

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    The problem is the voltage. A standard AAA battery is 1.5 volts, and the LED I used is 2.2 volts. It would not light up with the smaller voltage. I chose to use a larger voltage battery and step it down with a resistor. And the reflector will screw on, but not all the way, so I actually drilled the hole slightly larger to get it on 100%.