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

  1. #121

    Re: X-ray Film example and comparison.

    You would, of course, have to fix both sides of the negative after developing just one side.

    Also, I don't think the the xrays effect the film directly. Rather, they cause the holders to emit green or blue light (phosphoresce?). So, an anti-halation layer--necessarily on the outside of the emulsion so it can be washed off--would prevent one of the sides from being exposed.

  2. #122

    Re: X-ray Film example and comparison.

    Sure, I will try it when I have time, perhaps this weekend. I guess the question will be how much extra exposure to give it...

  3. #123

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    Re: X-ray Film example and comparison.

    Quote Originally Posted by Jason Greenberg Motamedi View Post
    You would, of course, have to fix both sides of the negative after developing just one side.

    Also, I don't think the the xrays effect the film directly. Rather, they cause the holders to emit green or blue light (phosphoresce?). So, an anti-halation layer--necessarily on the outside of the emulsion so it can be washed off--would prevent one of the sides from being exposed.

    You are correct, modern Xray work is done with film cassettes that have phosphor screens on both sides of the sheet of film, and under Xrays they emit blue or green phosphoresence that exposes the film. X-rays do not directly expose the film.

  4. #124

    Re: X-ray Film example and comparison.

    It doesn't look like there is a significant difference, but perhaps the limiting factor might be your lens. Half of a RR at f22 isn't all that sharp...

  5. #125

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    Re: X-ray Film example and comparison.

    So much for science- There doesn't seem to be a lot of difference and I hope that is true for contact prints.
    my goal is to shoot some 7x17 [after 8x10 experience] so I'd like to see some contact prints anyways- and maybe I can see my own by monday.
    Thanks for all the work!

  6. #126
    Wayne venchka's Avatar
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    Re: X-ray Film example and comparison.

    I could be wrong. Always a distinct possibility. Wasn't the double sided emulsion question raised earlier in this discussion? The conclusion, from folks in the know, was that the emulsion on the back of the film wasn't exposed and removed during fixing.

    It seems to me that even if there are traces of the second emulsion remaining, it just adds a bit of character to the x-ray film image. Use x-ray film because it looks like x-ray film. Does that make sense?
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  7. #127
    LF/ULF Carbon Printer Jim Fitzgerald's Avatar
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    Re: X-ray Film example and comparison.

    This is cool as far as testing goes. I have 4 images to develop this weekend of some well lit rocks shot with my 11x14 and some green sensitive film. I used my 15" Ilex process lens and the images were all shot at F-64 or 90. I have some carbon tissue ready to print these on if I have good images. I have a similar image done on Efke-25 from the same area in the same type of light. Nothing scientific but I am confident that I will have a great image to share by the end of the weekend. I don't care about the how or why. If I get a great image and can print it in carbon then I will be happy. If I can only print it in silver then I'll still be happy as I am really shooting my free 11x14 x-ray film. I already have a portrait that I shot of my son and I am completely happy with that so I expect that my 'Sharp" images will be just fine.

    Jim

  8. #128

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    Re: X-ray Film example and comparison.

    Here is an example of Konica PPB (IIRC) 7x14 cropped from a 7x17 neg. This is just a test, I haven't quite nailed down the exposure yet. Shot at 64 developed in D76 1:1 for 7 minutes. The neg would be perfect for silver printing.

  9. #129

    Re: X-ray Film example and comparison.

    Out of curiosity and some frustration with the occasional scratch I ordered one of the 11x14 hangers from here:
    http://www.quickmedical.com/wolf_xra...g_hangers.html
    It is well made, although as I suspected, it does pierce the negative in all four corners with a small hole. I will eventually make three dip tanks for the hanger.

  10. #130
    LF/ULF Carbon Printer Jim Fitzgerald's Avatar
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    Re: X-ray Film example and comparison.

    This is not the image I was referring to in the earlier post but it will do. I am reprinting this with the negative reversed on the same carbon tissue to see if there is any difference. It seems like in carbon there is some softening of the image. I do not have a problem with this and I think it will be okay for some of my future work.
    Eventually I will print this on some Azo to compare but I like the final result of the x-ray film. I developed the negative in a tray in Pyrocat-HD 1:1:200 for 15 minutes. It gave me a DR of 2.32. The range of contrast in the scene was about 3 stops. The image has some awesome relief. Still some more testing to do and I have to make the hangers for the 11x14 because I did get some scratching but so far I'm very happy.

    Jim

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