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

  1. #6111

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

    Quote Originally Posted by Tin Can View Post
    Too many unknown variables to consider any solution

    I use Green X-Ray which is NOT GREEN, as it is cheapest

    I use known shutters with known apertures and always consider bellows factor. I test my shutters with a discontinued iPhone gismo

    Daylight varies continuously, some meters are not correct

    I mostly shoot studio flash, same 4 for years, very stable

    A very good modern Sekonic Flash Meter is essential for me

    However in daylight I always guess exposure by Sunny 16, as I shot Sunny 16 ONLY for 40 years

    Then I check with Sekonic
    I'll check the shutter and verify. I am going to do some more experimenting at different film speed "ratings" and compare against "sunny 16" Just checked my notes exposure was f/16 at 1/25 second. Sunny 16 should have indicated 1/100 second at iso 100 film rating.

    Lots of variables and note taking ahead.

    I seem to have done pretty well with typical 4x5 films and roll films.

  2. #6112

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

    Quote Originally Posted by morecfm View Post
    Hello: I've kind of been lurking on this thread. I'm a first-time user of Fujifilm HR-U which also is my first time in 8x10 and tray developing. From previous reading elsewhere, I rated the film at ISO 100 and developed with HC-110 dilution B for 5 minutes. Results indicate over exposure by quite a bit. Also, as first time tray developing film, I dinged up the film during processing but I knew this was a possibility with this film. The film is drying now, so I will see how it scans tomorrow. I'm just wondering if I over exposed, over developed or a combination of both.

    I'm going to be doing some serious bracketing to see what will work the best if my developing time and strength are close to recommended.
    I rate this film around EI80-100 and develop in HC-110 1+47 for 6 minutes or 1+63 for 7 minutes.
    So if you are using Dil B time should be around 3 minutes.
    Hope this helps.

  3. #6113

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

    Hello all,

    I'm new to the site and to this thread, and I will soon be delving into X-ray film for use with a 5x7 camera (I ordered the Fuji 8x10 green film and intend to cut it to fit my holders).

    I plan on using D23 diluted quite a bit. Does anyone have any suggestions for dilution and development times? I've been clicking through the pages but haven't found this yet. Thanks!

  4. #6114

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

    Quote Originally Posted by the4x5project View Post
    I rate this film around EI80-100 and develop in HC-110 1+47 for 6 minutes or 1+63 for 7 minutes.
    So if you are using Dil B time should be around 3 minutes.
    Hope this helps.
    Thanks. This will give me a place to start over again. This is information I am looking for.

  5. #6115

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

    Quote Originally Posted by Tin Can View Post
    Too many unknown variables to consider any solution

    I use Green X-Ray which is NOT GREEN, as it is cheapest

    I use known shutters with known apertures and always consider bellows factor. I test my shutters with a discontinued iPhone gismo

    Daylight varies continuously, some meters are not correct

    I mostly shoot studio flash, same 4 for years, very stable

    A very good modern Sekonic Flash Meter is essential for me

    However in daylight I always guess exposure by Sunny 16, as I shot Sunny 16 ONLY for 40 years

    Then I check with Sekonic
    I'm getting some answers. I checked the shutter speed with an Iphone app with an optical adapter. 1/25 on the ilex lens was actually 1/5 and the compur shutter 1/9 second. A scenario ripe for over exposure. Now to keep the results with my kit. I need to learn to use longer shutter speeds with these lenses.

    Now to test my 4x5 kit. (more lenses, more work)

  6. #6116

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

    Testing old shutters is smart!
    The “green” refers to spectral sensitivity range and was intended to let the medical user know what kind of film holder with what specific phosphor lining to use to convert the X-rays to visible light to enhance sensitivity and lower the X-ray dose to the patient.
    Since your film doesn’t “see” the entire visible light spectrum your light meter, even if modern, will sometimes suggest incorrect exposures. Early in the day or late in the day it can be up to several stops wrong because the color of the light is more toward the red (insensitive) portion of the spectrum. Incandescent light or similar color temperature fluorescent or LED indoors will also do this. I’d expect studio flash to be better because it is more full spectrum and very repeatable.

  7. #6117

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

    Putting in front of the lightmeter's sensor a filter that cuts away the spectrum the film does not see, will it force the meter to give result more in the range of the film.
    In pracitcal terms: measuring trough a green filter will it give more accurate results, even late/early in the day?

  8. #6118

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

    Quote Originally Posted by Eugen Mezei View Post
    Putting in front of the lightmeter's sensor a filter that cuts away the spectrum the film does not see, will it force the meter to give result more in the range of the film.
    In pracitcal terms: measuring trough a green filter will it give more accurate results, even late/early in the day?
    green x-ray film is orthochromatic, so you want a cyan filter.

  9. #6119
    Tin Can's Avatar
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    Re: Use of X-ray film: technical discussion with example images

    Have you tried that?

    I have not

    I have not seen anything about it in the X-Ray thread

    Quote Originally Posted by maltfalc View Post
    green x-ray film is orthochromatic, so you want a cyan filter.
    Tin Can

  10. #6120

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

    Why cyan an not green?

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