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Thread: Use of X-ray film: technical discussion with example images

  1. #6411

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    Re: Use of X-ray film: technical discussion with example images

    Quote Originally Posted by Alan Townsend View Post
    Tin Can and xray film repurposers,

    I've been using these 6W LED Lamps as ortho safelights: https://www.amazon.com/gp/product/B0...0?ie=UTF8&th=1

    Current price is $5.99 for a two pack. These lamps are internally true red LED and have red bulb filter as well. Do not fog ortho litho film at 3 ft. distance. Do not fog FUJI HR-U indirectly at 8 feet with film exposed face up for 12 minutes.

    The are not claimed to be safelights but work very well. FYI I continue to use caution. Thanks for all the information.
    Good day all. Following on reading this I investigated what could be found in my area of Victoria Canada. Home depot had a color selectable led light with a red setting. I find this to be way to bright in my grow tent darkroom. I found a FEIT 4.5 watt red led light bulb at Lowes. It has the advantage of being dimmable. I also found a Lowes an extension cord equipped with a led dimming switch. Together I am able to go from off to barely on and then steplessly to full on. In a reflector housing this gives me all the light versatility I need. I corresponded with FEIT electric and requested a spectral emission data for this bulb. I reproduce this below. I have also added the spectral sensitivity for the Fuji X-ray film I use as well as that for Ilford ortho film for comparison purposes.

    Regards
    Attached Thumbnails Attached Thumbnails Ilford ortho spectrum.JPG   Spectral sensitivity Fuji xray film.JPG   Red Feit led light spectrum.JPG  

  2. #6412
    Tin Can's Avatar
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    Re: Use of X-ray film: technical discussion with example images

    I usw my Sekonic spot meter all the time for falloff afd make simple center filters for enlarging

    simple masks too
    Tin Can

  3. #6413
    Tin Can's Avatar
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    Re: Use of X-ray film: technical discussion with example images

    Tin Can

  4. #6414
    おせわに なります! Andrew O'Neill's Avatar
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    Re: Use of X-ray film: technical discussion with example images

    Quote Originally Posted by Alan Townsend View Post
    Tin Can and xray film repurposers,

    I've been using these 6W LED Lamps as ortho safelights: https://www.amazon.com/gp/product/B0...0?ie=UTF8&th=1

    Current price is $5.99 for a two pack. These lamps are internally true red LED and have red bulb filter as well. Do not fog ortho litho film at 3 ft. distance. Do not fog FUJI HR-U indirectly at 8 feet with film exposed face up for 12 minutes.

    The are not claimed to be safelights but work very well. FYI I continue to use caution. Thanks for all the information.
    Excellent! Thank you for the link to the LED bulbs!

  5. #6415
    おせわに なります! Andrew O'Neill's Avatar
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    Re: Use of X-ray film: technical discussion with example images

    I was at the dentist for cleaning and checkup yesterday. I was pleased to see that they still use xray film.

  6. #6416
    Pastafarian supremo Rick A's Avatar
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    Re: Use of X-ray film: technical discussion with example images

    My previous dentist went digital, missed a cavity that went undiscovered until my new dentist saw it ON FILM. Sensitive tooth is now fixed.
    Rick Allen

    Argentum Aevum

    practicing Pastafarian

  7. #6417

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    Re: Use of X-ray film: technical discussion with example images

    Sorry to hear about dental problems. The FUJI HR-U I recently purchased 100 sheets 8x10 from an ebay dealer for $42 with shipping included comes from Australia, according to box information.

    While here in the US, most medical use is shifting or has shifted to digital, this is not happening worldwide for obvious economic reasons. In the US, we have the worst medical care at the highest possible cost of any country on earth. I'm sure that China and India will remain xray film users for many years. Countries with national health care system, may also do the same for cost control in various degrees. In the US, rural health care, and portable services will continue its use. I believe xray film will be around for quite some time, maybe 10-20 years or more. Also veterinarians.

    Fortunately, Xray is a contact printing process, since xrays are not imaged with lenses, so requires very large films. From my reading, xray film exposes patients to less radiation, provided a single exposure is adequate. Xray use recycles silver very effectively well, since they do scan the xrays for archiving. Imagine the cost of a 14 by 17 digital sensor.

  8. #6418

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    Re: Use of X-ray film: technical discussion with example images

    What about using a red laser as darkroom light? I see laser modules on sale for different wavelenghts, including red ones. They are specified for an exact wavelenght, so this could be an advantage.
    Is my idea stupid or could it work? I see some of the lasers are unfocussed, I guess these have a larger beam and oriented to the ceiling maybe it could work.

  9. #6419

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    Re: Use of X-ray film: technical discussion with example images

    Quote Originally Posted by Eugen Mezei View Post
    What about using a red laser as darkroom light? I see laser modules on sale for different wavelenghts, including red ones. They are specified for an exact wavelenght, so this could be an advantage.
    Is my idea stupid or could it work? I see some of the lasers are unfocussed, I guess these have a larger beam and oriented to the ceiling maybe it could work.
    Eugen, that could work provided they output a few watts of light. Are they affordable at that power level? Also, the laser speckles could be a problem, since they make it harder to see details.

  10. #6420

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    Re: Use of X-ray film: technical discussion with example images

    I don’t think a red laser would be a good choice for a darkroom light: too bright, too focused. Lasers want to be linear. A few watts of laser light would be extremely dangerous because of the focused nature. Light bulbs radiate in all directions, so they don’t get dangerous at a few watts. Laser pointers are 1/1000th of a watt or so, I think. This thread has at least one discussion of LED low power red bulbs as darkroom lights. I’m pretty sure you will need to order them from a special dealer on line.

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