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Thread: Darkroom Safe Light

  1. #11
    David Schaller
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    Mar 2002
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    Re: Darkroom Safe Light

    Quote Originally Posted by sabeluc View Post
    Are the super bright LEDs safe for X-Ray film?
    I found that having a red LED on while I developed X-ray film created fog, so I haven't used it since. Some people have mentioned turning on the red safelight after about three quarters of the development time, but I haven't bothered. I might experiment with the safelight again were I to try cutting down 8x10 X-ray film, but I would remove only a couple of sheets from the box in total darkness before I did so.

  2. #12
    John Olsen
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    Re: Darkroom Safe Light

    After reading this thread I saw the red LED at the hardware store, so I tried it. Even at 4.5W, aimed at the back wall and 9' away from the enlarger it's just too bright. I tested it for safeness with my Ilford paper and it was OK out to about 4 minutes once I laid a sheet of mylar over the lamp. However, it's still bright enough that I can't see the image projected down on the easel well to do accurate burning and dodging. I took it out and went back to my ancient safelight. Maybe I'll try it again with more attenuation.

  3. #13

    Join Date
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    Re: Darkroom Safe Light

    if your LED is small, you can stick ND filters in front of it to precisely control brightness. I've used this trick for preflashing paper negatives using a small desk lamp pointed at the ceiling.

    I did a few tests today on X-Ray film with my Halco safelight bulb. Though it was subtle, I do believe it fogged the X-Ray film. I pulled a sheet out in darkness, sliced a strip off and put it in the developer. I then sliced another strip off and turned on the safelight, holding it out to make sure it was well exposed. The one with direct safelight exposure was a little bit foggier after about 5 min in HC-110 Dilution H. I'm not sure in a well exposed negative I would be able to detect the fogging, but it would certainly reduce overall contrast. FWIW, I wasn't very careful with the experiment but there was enough fogging that I believe the Halco safelight with no filter is an issue for X-Ray film.

    It would be great to know of a light that was totally safe.

  4. #14
    Tin Can's Avatar
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    Dec 2011
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    Re: Darkroom Safe Light

    Doubtful any safe light is 100% bulletproof

    Just like all things photographic, intensity, spectrum and time which together is 'dwell' is always important

    Even in complete dark loading film holders and unloading them into my developer I don't waste time, only seconds of time is necessary

    Be quick
    wear mask or NOT

    is ???

  5. #15

    Re: Darkroom Safe Light

    I fogged some Ilford Commercial Ortho with my old Paterson safelights, so I knew I needed something safer....

    Jason Lane (the dry plate manufacturer) knows exactly what he is talking about. I ordered a batch of his ASA 25 glass "Speed Plates" and was waiting for shipment. He emailed me that he had to toss and re-do coating more plates, they were ruined by safelight fog. He then told me what he made up as a replacement. I followed his lead, and I'm delighted, no fog even after eighteen minutes of development, with lamp six feet away. Go with the 3 watt LED from Lowes, and it goes into the Kodak Bullet Safelight, with the dark red 1A filter. So it's a 3W LED, being additionally filtered by the dark red Kodak 1A. VERY VERY deep red light is emitted and I have have zero fogging now. I have one in one corner for film cutting and loading, and one over the developer tray, both more than six feet away. And more than bright enough once my eyes adjust, I can hold a sheet up and inspect the shadow values quite accurately. Works great for me!

    3W LED from Lowes:
    https://www.lowes.com/pd/Energetic-W...ulb/1000623747

    Thanks for this Jason Lane!

    Kodak 1A Grey Bullet Safelight 1 by Nokton48, on Flickr

    https://www.lowes.com/pd/Energetic-W...ulb/1000623747

    Kodak 1A Grey Bullet Safelight 2 by Nokton48, on Flickr
    “The secret of getting ahead is getting started.”
    ― Mark Twain

  6. #16

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    Re: Darkroom Safe Light

    This morning, I tested some X-ray film with a red LED (in a headlamp) bounced off the ceiling and with direct exposure at close range to the LED.

    I found the film that was exposed to ambient LED light only during 5 min of development in HC-110 Dilution H to be free of fog to my eye. The film that was exposed directly was severely fogged but only down the center where the beam of light hit it. The edges seem to be as clear as the ambient-only film.

    My conclusion is that ambient light from a red LED is safe for x-ray film. Close range direct exposure is not safe, but you have to go out of your way to achieve this. This is really good news because I think it is nearly impossible to avoid scratching large sheets of film while cutting and loading it without a safe light.

    In contrast, the same experiment with my Halco incandescent safelight produced a fully black exposed negative and is not safe at all for X-Ray film.

    Click image for larger version. 

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  7. #17

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    Re: Darkroom Safe Light

    The super bright LEDs are back in stock in case anyone was waiting.

  8. #18

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    Feb 2013
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    Re: Darkroom Safe Light

    I may have asked this before-are the Superbrite amber bulbs Ok for darkroom use?

  9. #19

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    Aug 2019
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    Tillsonburg, Ontario
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    Re: Darkroom Safe Light

    Quote Originally Posted by MrFujicaman View Post
    I may have asked this before-are the Superbrite amber bulbs Ok for darkroom use?
    The web page says that the amber led wavelength is 596nm
    Check the information page of the paper / film you will be using to see if this wavelength is safe
    I use Ilford paper and the specs say they are not sensitive to wavelengths above 550nm
    So the amber should be ok, you will never know unless you test
    In my darkroom I have 8 red leds on at all times putting out wavelengths of 631nm
    No paper fogging and it is SuperBright

    Dan

  10. #20

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    Re: Darkroom Safe Light

    I have just ordered a few amber S11 bulbs and will test and post. I use Ilford Warmtone fiber.
    Philip U.

    Sine scientia ars nihil est. (Without science/knowledge, art is nothing.)
    https://www.flickr.com/photos/156933346@N07/

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