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  1. #31

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    I use a very bright red LED - probably 1 W and it will fog my ISO 3 homemade emulsions (which are not pan) if left withing 1 inch for 30 seconds. About the same for paper. I've never had any issue with fog at all, for any length of time (including the 2 or 3 hours it takes to make a liquid emulsion) at distances greater than a foot. For B&W papers and lower speed ortho films, there is very little risk of fog with Red LED's in my experience. You have to actually try to fog the paper/ortho film. I use the same light with Arista Ortho film quite often, and have suffered no ill effects.

  2. #32
    PeterB's Avatar
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    Quote Originally Posted by DaveOttawa View Post
    I've attached the SED of a flashlight that I measured
    Dave, how did you measure that ? I've had a few LESs with different centre frequencies I've had for a while, wondering what I would use to measure their response.

    Rgds Peter.

  3. #33
    Mainecoonmaniac's Avatar
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    I bought a set of red LEDs and strung them in my darkroom as safelights. It works well. I ran a test of exposing a sheet of paper for an hour with no fogging. You can also get orange LEDs too. I stopped using my Thomas Duplex safelight because the LEDs are so bright.

    Take a look:
    http://www.ebay.com/itm/Fad-Red-20M-...item3f20e362a2
    "Photography, like surfing, is an infinite process, a constantly evolving exploration of life."
    Aaron Chang

  4. #34

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    Do a proper safelight test as per Kodak's instructions prior to using LED safelights.

  5. #35
    Ken Nadvornick's Avatar
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    Or even the quick-and-dirty CD test. You might be surprised.

    Ken
    "They are the proof that something was there and no longer is. Like a stain. And the stillness of them is boggling. You can turn away but when you come back they’ll still be there looking at you."

    — Diane Arbus, March 15, 1971, in response to a request for a brief statement about photographs

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