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

  1. #6431
    chris73's Avatar
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    Re: Use of X-ray film: technical discussion with example images

    Quote Originally Posted by Eugen Mezei View Post
    Another silly question: Could those ir lamps used for heating be of use in the lab? They emit red light but I dont know if only that or white light also.
    Bounce the light on a cd/dvd surface and see if there are present other colors than red.

  2. #6432

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

    Quote Originally Posted by Eugen Mezei View Post
    Another silly question: Could those ir lamps used for heating be of use in the lab? They emit red light but I dont know if only that or white light also.
    Why do you not order those:
    https://www.fotoimpex.com/darkroom/a...oom-light.html

    I have them installed in simple IKEA lamps and they work fine. To be sure I illuminate the white ceiling and walls with them only.

    Hope this helps.

  3. #6433

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

    Quote Originally Posted by the4x5project View Post
    Why do you not order those:
    https://www.fotoimpex.com/darkroom/a...oom-light.html

    I have them installed in simple IKEA lamps and they work fine. To be sure I illuminate the white ceiling and walls with them only.

    Hope this helps.
    I see they are good for paper, but I don't see a reference to X-Ray film. Have you tested with film and found them safe?

  4. #6434

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

    Quote Originally Posted by the4x5project View Post
    Why do you not order those:
    https://www.fotoimpex.com/darkroom/a...oom-light.html
    I have them installed in simple IKEA lamps and they work fine. To be sure I illuminate the white ceiling and walls with them only.
    The reason is, I already have the IR lamps. (And can buy more of them locally.) Ordering from Fotoimpex would mean around 30 €.
    Besides that, I am curious.

  5. #6435

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

    I have bought a kit (developer + fixer) for X-ray film. Looking at the chemical composition I see in neither of them a hardener. I thought X-ray film is hardened when developing, either in the developer or at least in the fixer.

  6. #6436

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

    I think X-Ray film is just prone to scratches when wet. I doubt hardener in fixer does much good as the film has already been wet in the developer and stop for several minutes. I think being careful with process is better than depending on chemicals.

  7. #6437

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

    Still hardener for fixer exist. On the bottle of the Tetenal hardener they even give the time for X-ray film. (They are longer as for normal film.)
    Did I have with you the discussion on Flickr? (In the Polypan-F group.) As there were also two posters thinking that the hardening effect dissapears after the film is dry.

  8. #6438

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

    I don't use Flicker. I don't say the hardening effect disappears. The film becomes really prone to scratching when wet - thus it can scratch in the developer and stop long before it gets to the fixer. Hardening fixer is fine to use but may not stop scratches.

  9. #6439

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

    Quote Originally Posted by j.e.simmons View Post
    I see they are good for paper, but I don't see a reference to X-Ray film. Have you tested with film and found them safe?
    Yes, I did. Works fine with x-Ray and all things orthochromatic.

  10. #6440

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

    Things I like about Xray film, other than cost. (green HR-U)

    1. After processing, this film lies flatter than any film I've ever used (4x5), even though it's a bit thinner than normal photo film. Likely due to being equally coated on both sides. Open frame negative carriers in enlarger work OK. No need for single glass carriers.

    2. Loss of sharpness compared with normal photo film is likely due to halation. This film doesn't scatter light very much but is very reflective compared with normal films. This favors use of very small f-stops like f-32 over larger, due to smaller cones of light. I get pretty good sharpness from 3x enlargements.

    3. Develops nicely with low agitation. This allows semi-compensating developers to produce better sharpness. D23 at 1:7 dilution for 20 mins. at STP works well at ei 100 in Doran developing tank with 12 films at a time. Almost a stand development. Yankee tank would be similar.

    3. Fixes quickly (5 min.) in low concentration plain fixer. I use about 30 grams sodium thiosulphate per 52 fluid ounces. This low concentration washes out very fast as well.

    4. I remove films from tank after washing and hang to dry. Drying in tank holder takes too long, about 4 days, so I stopped doing that. Careful and slow extraction gives few scratches or mars along edges.

    Alan Townsend

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