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  1. #1

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    Brilliant White: safe for darkroom walls?

    This is probably just a stupid question, but I guess it's best to be sure. I'm just about to paint the walls of my new darkroom. It occurs to me that Brilliant White contains optical brighteners. As far as I understand, these are basically fluorescent materials that absorb energy at UV wavelengths and re-emit it within the visible range of wavelengths. Since amber/red safelights are at the other end of the visible spectrum, can I safely assume that these optical brighteners are 'safe' in a darkroom?

  2. #2
    cliveh's Avatar
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    Quote Originally Posted by Jonathan R View Post
    This is probably just a stupid question, but I guess it's best to be sure. I'm just about to paint the walls of my new darkroom. It occurs to me that Brilliant White contains optical brighteners. As far as I understand, these are basically fluorescent materials that absorb energy at UV wavelengths and re-emit it within the visible range of wavelengths. Since amber/red safelights are at the other end of the visible spectrum, can I safely assume that these optical brighteners are 'safe' in a darkroom?
    Yes. However, quantum mechanics may not agree.
    Last edited by cliveh; 01-20-2013 at 03:52 PM. Click to view previous post history.

    “The contemplation of things as they are, without error or confusion, without substitution or imposture, is in itself a nobler thing than a whole harvest of invention”

    Francis Bacon

  3. #3
    RalphLambrecht's Avatar
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    white walls are perfectly fine for a darkroom. the only place where you may need black paint is around the enlarger.
    Regards

    Ralph W. Lambrecht
    www.darkroomagic.comrorrlambrec@ymail.com[/URL]
    www.waybeyondmonochrome.com

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    cliveh's Avatar
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    Quote Originally Posted by RalphLambrecht View Post
    white walls are perfectly fine for a darkroom. the only place where you may need black paint is around the enlarger.
    And the light trap entrance.

    “The contemplation of things as they are, without error or confusion, without substitution or imposture, is in itself a nobler thing than a whole harvest of invention”

    Francis Bacon

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    What about blue walls, would safelight hitting them be reflected as unsafe light?

  6. #6
    cliveh's Avatar
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    Quote Originally Posted by Ed Bray View Post
    What about blue walls, would safelight hitting them be reflected as unsafe light?
    No and why would you want blue walls in a darkroom?

    “The contemplation of things as they are, without error or confusion, without substitution or imposture, is in itself a nobler thing than a whole harvest of invention”

    Francis Bacon

  7. #7

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    They would come up as black since there would be no blue light to reflect. Red however would be a great darkroom paint, as it would reflect only safe light even if your safelight were unsafe.
    Of course this is not a perfect world and few things emitting and reflecting are precisely as they seem.
    "There are a great many things I am in doubt about at the moment, and I should consider myself favoured if you would kindly enlighten me. Signed, Doubtful, off to Canada." (BJP 1914).

    Regards
    Bill

  8. #8
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    The key point here is not what color the walls are, it's what color the walls reflect.

    If all of the possible sources of light in a darkroom are safe (by whatever definition of "safe" is required for the process being performed), then by definition the walls—regardless of their color—cannot reflect an unsafe color. In this case any color will do. But white is preferred to spread the "safe" light around more efficiently.

    The problems arise when one has white walls and the enlarger leaks imaging light. Or the doorframe leaks white light. Or the safelights aren't really totally safe. Then white walls only make the problem worse. In those cases black would be the ideal color, because you'd want to limit the spread of the "unsafe" light as much as possible.

    Regarding the OP's question about UV causing optical brighteners to emit light from the walls, I've never heard of this being a problem. But the guaranteed solution would, of course, be to simply add UV light to the set of "unsafe" light colors and eliminate it from the darkroom the same as regular white light. And amber/red, not being UV, should have no practical effect.

    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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    Quote Originally Posted by cliveh View Post
    No and why would you want blue walls in a darkroom?
    Perhaps if your Darkroom were dual use, say a bathroom or bedroom with Blue Walls but occasionally used as a darkroom. Not everyone has the space for a seperate darkroom. The question was just something that occured to me.

  10. #10
    cliveh's Avatar
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    Quote Originally Posted by Ed Bray View Post
    Perhaps if your Darkroom were dual use, say a bathroom or bedroom with Blue Walls but occasionally used as a darkroom. Not everyone has the space for a seperate darkroom. The question was just something that occured to me.
    A good point to which I agree.

    “The contemplation of things as they are, without error or confusion, without substitution or imposture, is in itself a nobler thing than a whole harvest of invention”

    Francis Bacon

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