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

  1. #5521

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

    Quote Originally Posted by blue4130 View Post
    Attachment 202465Attachment 202466Attachment 202467

    There are all Fuji x-ray developed in HC110
    Amazing results, my dear friend
    You are a true creator.
    I was hoping for a positive reversal picture, transparent

  2. #5522
    Corran's Avatar
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    Re: Use of X-ray film: technical discussion with example images

    Quote Originally Posted by mohmadkhatab View Post
    I was hoping for a positive reversal picture, transparent
    In case it hasn't been clear, no one here seems to be pursuing positive images from x-ray films, for reasons already enumerated. You are on your own, so test, test, test, and let us know how it goes so we can copy your process.
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    All comments and thoughtful critique welcome

  3. #5523
    Recovering Leica Addict seezee's Avatar
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    Re: Use of X-ray film: technical discussion with example images

    Quote Originally Posted by mohmadkhatab View Post
    There are two types of developers that can be used in hospitals.
    There is a type called (automatic) which is used by an acidizing device. And it is really very fast.
    There is another type called (manual), and it is still used manually in poor hospitals that do not have this automatic acid developing device.
    The second type is slow and depends on the expertise of the radiologist in developing x-rays. He develops under the red light and knows when it was developed and finishes the process.
    I think this type is very important if it is lightened by a large percentage perhaps giving us another vision that we did not know.
    I did not know about the latter type. You would probably get decent results with it after some trial-and-error.
    "Never try to teach a pig to sing. It wastes your time and annoys the pig."

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  4. #5524

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

    Mohmadkhatab,
    I recommend that you check posts # 4873, #5389, and #5391 in this thread, you might find them to be helpful and informative. Best of luck!

  5. #5525

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

    Quote Originally Posted by Corran View Post
    In case it hasn't been clear, no one here seems to be pursuing positive images from x-ray films, for reasons already enumerated. You are on your own, so test, test, test, and let us know how it goes so we can copy your process.
    You are absolutely right ,,
    Acids are available, I prepare it from scratch.
    The camera is still not clear yet, and I did not settle for one while I am confused about this and that and the prices are different and Corona caused total paralysis in the country.

  6. #5526

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

    Quote Originally Posted by Dugan View Post
    Mohmadkhatab,
    I recommend that you check posts # 4873, #5389, and #5391 in this thread, you might find them to be helpful and informative. Best of luck!
    God bless you and thank you very much for the advice.

  7. #5527

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

    Quote Originally Posted by Justin K View Post
    A friend of mine is a physician and recently unearthed the xray film photo I've pasted below when cleaning out an old medical office. I know nothing about xray film, so I'm curious if anyone knows how an image like this one may have been made--a large positive image on xray film. We also have no idea who took this and where or when it was taken, so if any boating or marina experts out there detect and clues, please share.

    Thanks for any insights on this!

    Attachment 173228
    I am currently trying to do these tests to convert the X-ray film directly into a positive film without re-imaging during printing or the like.
    I am currently in the stage of collecting information, maybe using the method of our colleague in the forum who relied on the positive Ilford (PQ) recipe, or relying on the process Agfa Scala ,,, under study and research, we will see ..

  8. #5528

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

    Mohmad, I just did a quick test (I had to wait for my girlfriend to get ready for breakfast...)


    This is Ektascan B/RA xray film, single sided. Exposed at around EI 12 or so (I normally rate it at 50 for negatives).
    First development: in paper developer (a mix of leftovers), ca. 90 seconds - development essentially to completion.
    After stop bath (acetic acid) turned on the lights for further processing.
    Bleach: dichromate + sulphuric acid
    Redevelopment: same developer as for the initial development, again to completion.

    Notice a few things:
    * The image is fairly dark. This is basically because there's way too much silver halide left after the first development step (and bleaching), even despite the pretty dramatic overexposure.
    * The edges are too light. This is due to the use of a concentrated developer and a suboptimal agitation scheme in the first development step. Can easily be resolved by using a more dilute developer and intermittent agitation. But I just did a quick & dirty test.
    * Contrast is on the low side, but it's also a low contrast scene to begin with. So overall quite realistic.

    The excess overall density is the main issue, and it can be solved by adding a silver solvent (e.g. sodium thiosulfate) to the first developer, or, alternatively, partly fixing the negative in a dilute thiosulfate solution before the first development step. The exact parameters (thiosulfate concentration + fixing time) need to be tailored to the film and the desired contrast. I did not do any of this testing; it involves a systematic approach. As I did this test in a matter of half an hour or so, I didn't bother with it. But to optimize the results, it is required.

    Here's the same piece of film held up to the window and photographed with my crappy phone:

  9. #5529

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

    Quote Originally Posted by koraks View Post
    Mohmad, I just did a quick test (I had to wait for my girlfriend to get ready for breakfast...)


    This is Ektascan B/RA xray film, single sided. Exposed at around EI 12 or so (I normally rate it at 50 for negatives).
    First development: in paper developer (a mix of leftovers), ca. 90 seconds - development essentially to completion.
    After stop bath (acetic acid) turned on the lights for further processing.
    Bleach: dichromate + sulphuric acid
    Redevelopment: same developer as for the initial development, again to completion.

    Notice a few things:
    * The image is fairly dark. This is basically because there's way too much silver halide left after the first development step (and bleaching), even despite the pretty dramatic overexposure.
    * The edges are too light. This is due to the use of a concentrated developer and a suboptimal agitation scheme in the first development step. Can easily be resolved by using a more dilute developer and intermittent agitation. But I just did a quick & dirty test.
    * Contrast is on the low side, but it's also a low contrast scene to begin with. So overall quite realistic.

    The excess overall density is the main issue, and it can be solved by adding a silver solvent (e.g. sodium thiosulfate) to the first developer, or, alternatively, partly fixing the negative in a dilute thiosulfate solution before the first development step. The exact parameters (thiosulfate concentration + fixing time) need to be tailored to the film and the desired contrast. I did not do any of this testing; it involves a systematic approach. As I did this test in a matter of half an hour or so, I didn't bother with it. But to optimize the results, it is required.

    Here's the same piece of film held up to the window and photographed with my crappy phone:
    You are awesome, man.
    Very very great ,,
    God bless you ,
    - If you allow me ,,
    I have some remarks, I hope your chest expanded to listen to it.
    I find myself more inclined to use potassium thiocyanate instead of sodium thiosulfate, as it means more accurate results.
    - I think that the idea that the first developer is the same as the second developer has proven to be a failure of that idea a lot,
    - The first developer should contain potassium thiocyanate or sodium thiosulfate (I prefer the first), while the second developer does not contain this component.
    - The image still has a lot of silver, as the bleaching is not sufficient, (the time of bleaching is small or the focus of the bleach is weak or both reasons)
    The second re-exposure was weak as I thought and relied only on completing the steps with room light (as I think), and this is not enough, the second re-exposure should be done in a concentrated manner and preferably chemical and not dependent on room lighting because re-exposure is using Room lighting will not result in equal and equal exposure in all parts of the film, and accordingly, the image will be a hybrid of negative and positive anonymously.
    This is what I thought happened to you,

    In any case, you are a great and wonderful man. You were thrown in a stagnant pool.
    - This experience will excite the rest of the colleagues to provide more tests, and this is very amazing.
    - I got a piece of the camera and the rest of the camera is not available yet, and I want to consult you, what is that piece and is it compatible with all cameras?
    God bless you
    NB :
    Regarding the re-exposure step.
    I support the chemical method.
    By adding one gram of tin chloride to the second developer.
    Work in complete darkness in all steps.
    Click image for larger version. 

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  10. #5530

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

    Quote Originally Posted by mohmadkhatab View Post
    You are awesome, man.
    Very very great ,,
    God bless you ,
    - If you allow me ,,
    I have some remarks, I hope your chest expanded to listen to it.
    Many thanks, Mohmad, for your kind words and for sharing your thoughts. Please allow me to respond on them:

    I find myself more inclined to use potassium thiocyanate instead of sodium thiosulfate, as it means more accurate results.
    - I think that the idea that the first developer is the same as the second developer has proven to be a failure of that idea a lot,
    - The first developer should contain potassium thiocyanate or sodium thiosulfate (I prefer the first), while the second developer does not contain this component.
    Yes, I agree. The first developer should ideally contain a silver solvent, or alternatively a separate silver solvent process step should be performed before the bleach step. I think the choice between thiocyanate and thiosulfate is perhaps a personal one; why would you prefer thiocyanate?

    - The image still has a lot of silver, as the bleaching is not sufficient, (the time of bleaching is small or the focus of the bleach is weak or both reasons)
    I do not think the bleaching was insufficient. It was essentially complete, and this was easily verified visually since bleaching was done under normal light. Additionally, dichromate bleach is always very fast and effective in my experience.

    The second re-exposure was weak as I thought and relied only on completing the steps with room light (as I think), and this is not enough, the second re-exposure should be done in a concentrated manner and preferably chemical and not dependent on room lighting because re-exposure is using Room lighting will not result in equal and equal exposure in all parts of the film, and accordingly, the image will be a hybrid of negative and positive anonymously.
    In the image shown, I turned on the room lights after the stop bath and kept them on for processing. Note that my room lights are very bright indeed and exposure to them will fully expose any film, no matter what speed, within a second or so. In a subsequent experiment I reduced the exposure by a controlled one-second exposure to my room light. The effect was identical. This suggests that the fogging exposure was complete in both instances.

    Regarding the re-exposure step.
    I support the chemical method.
    By adding one gram of tin chloride to the second developer.
    Yes, I would prefer a chemical fogging step as well. Sadly, I do not have any tin chloride on hand. I might give it a try with sepia toner, but this of course modifies the image tone and adds some density as well on top of the silver image alone.

    As to your question on the equipment: it looks like a grafmatic 4x5" film holder. I have never used them, but as far as I understand, it is basically a standard 4x5" film holder with a little number dial that can be used to identify individual holders by exposing a number on each film sheet. I know that one or more people on this forums use these holders. I don't know in which cameras they may or may not fit. I mostly use Lisco Regal film holders.

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