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

  1. #3941
    Large Format Rocks ImSoNegative's Avatar
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    Re: Images shot on X-ray film

    Thanks renato after experimenting with it for a while I have learned that at one second you have to add a stop so far that has worked up to one hour. I tried straight time of course that didn't work so I tried after 3 or 4 sec start adding a bit of time. Its actually from one sec on add one stop all the way up so far to 30 min which is what I did last night. Longest so far. 1 hour in freezing cold but it was worth it
    "WOW! Now thats a big camera. By the way, how many megapixels is that thing?"

  2. #3942

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    Re: Images shot on X-ray film

    I think the Beseler 45 enlarger wants at least a 30" door with a standard base, 32 or 36 should keep you from having to take door off hinges and avoids skinned knuckles too. The mostly unused college darkroom where my son goes to school has an Omega 45, I didn't measure it. It was taller and I doubt the base was smaller.

    Contact prints? A UV light source big enough for 16x20 or at least 14x17 is smaller and lighter than the enlarger and many contact printing processes only need a dim room once your film is developed.

  3. #3943
    http://www.spiritsofsilver.com tgtaylor's Avatar
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    Re: Images shot on X-ray film

    My Beseler 45MXT measures 24-2/16" across and fits perfectly in the bedroom in the corner next to the entrance door - completely out of the way and invisible until you enter. For the first week I also put it in the bathroom but quickly came to the conclusion that was the wrong spot for it. Not only is it the most humid area of the apartment (taking shower, etc) but also the most smelliest (when you do you know what in there). that frees up the bathroom for the wet side of processing. I simply expose the paper in the bedroom where i have aa small safe light set up so that I can see the easel when printing B&W, put the exposed sheet in a paper safe and walk it across the hall to the bathroom where I have the trays set-up with a Thomas safe-light. For color RA-4 I put the exposed sheet in a Jobo tank and walk it to the processor set-up in the kitchen. A viewing station is set-up on the desk in the living room to evaluate the color for correction. Alternative prints are coated and dried in the bathroom and exposed to the sun outside and processed in the bathroom.

    Thomas

  4. #3944

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    Re: X-ray Film example and comparison.

    Camera is set for infinity focus? Permanently?
    What 450 that covers 14x17 @ infinity?
    Also, I'd suggest some washers or a board inside the camera to keep the screws from so easily pulling through the cardboard. Cool entry into the 14x17 format.
    I've thought about meniscus lenses with small stops, and pinholes as ways to further reduce cost.
    And, taping or magnets to hold a single sheet in the box to avoid holder cost.
    For such a camera suitcases at thrift stores with latches not zippers start to be attractive...

  5. #3945

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    Re: X-ray Film example and comparison.

    Also, gaffers tape is not 100% secure on cardboard or even metal and I d hate for you lens to peel off. I'd like to see some wood/screw sandwiches top/bottom holding it on.
    None of which is to take anything away from the diy coolness. Good job!

  6. #3946

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    Re: X-ray Film example and comparison.

    Quote Originally Posted by Fr. Mark View Post
    Camera is set for infinity focus? Permanently?
    What 450 that covers 14x17 @ infinity?
    Also, I'd suggest some washers or a board inside the camera to keep the screws from so easily pulling through the cardboard. Cool entry into the 14x17 format.
    I've thought about meniscus lenses with small stops, and pinholes as ways to further reduce cost.
    And, taping or magnets to hold a single sheet in the box to avoid holder cost.
    For such a camera suitcases at thrift stores with latches not zippers start to be attractive...
    Quote Originally Posted by Fr. Mark View Post
    Also, gaffers tape is not 100% secure on cardboard or even metal and I d hate for you lens to peel off. I'd like to see some wood/screw sandwiches top/bottom holding it on.
    None of which is to take anything away from the diy coolness. Good job!
    Thanks,

    Going in reverse.

    The taped board wasn't permanent, it held well though, mostly because the lens weight was centered well so it wasn't front heavy, Nikkor 450mm M seems to fully cover wide open.

    I purposefully kept a toyo to Linhof technika adapter board when I sold my toyo45a and I plan to permanently affix that to my future camera, however I'm probably going to go with a more reasonable "fancy" design in the future, this whole video came from a discussion a while back on here from someone who said it couldn't be done for cheap, so challenge accepted

    Because of the way the T frame and square frame come together at the L, I really didn't even need the screws, it was pretty solid without them, the screws were more just so that it prevented any vibration keeping the cardboard flush to the T frame wood. But good observation and point taken.

    The old American Standard travel hard cases are certainly a thought. Would make a kick ass wide angle, that's for sure!

    I was just talking about this on Facebook. Before I had real holders for my 11x14 design (where the box originally came from) I had a cardboard holder with corner tabs, magnets make a lot more sense, but can still slide if jarred.

    The old holder...

    Click image for larger version. 

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    Image from it, remember it was a pinhole at the time, but this shows the "holder edge markings" or rather corner markings, think of it like a business card that is held inside a folder.

    Click image for larger version. 

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    Finally, again I got the same question on Facebook, basically I set the focus for what I thought would be the kind of focus point I would want from a shot from this format, it wasn't hyperfocal exactly, it was just the kind of framing I tend to do and the kind of distance I tend to lean toward having a focus point on. Then I just move the camera back and forth until the object I want is in focus, stop down to give more depth but you probably won't really get full depth clarity with such a wide area, that and diffraction which doesn't REALLY do as much damage as people tend to claim because you're contact printing this kind of size, so it's not as much an issue IMO. Either way I set the focus for my style, YMMV as they say.

  7. #3947

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    Re: Images shot on X-ray film

    Seezee,
    Contact printing and enlarging, are two very different things.
    For the first one, all you need is a light source connected to a timer. Any, and I mean that literally, any enlarger will do.
    For enlarging, things get complicated fast. If you need more info on that, let me know.
    My suggestion was for contact printing only.

  8. #3948

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    Re: Images shot on X-ray film

    5 hours exposure on Agfa x-ray film, with a 135mm Optar at f/4.7 on a 4×5″ Speed Graphic.
    Tray developed for 10min in D76 (1+5) at 24C, with minimal agitation.
    Scan from negative, finished in PS.

    This was a test for nightscapes with very long exposures.
    Obvious marks of uneven development and scratches from handling.


  9. #3949
    Large Format Rocks ImSoNegative's Avatar
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    Re: Images shot on X-ray film

    very cool!!
    "WOW! Now thats a big camera. By the way, how many megapixels is that thing?"

  10. #3950

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    Re: Images shot on X-ray film

    In this instance you can just tell people that you were shooting the Northern Lights. :-)
    Thanks, but I'd rather just watch:
    Large format: http://flickr.com/michaeldarnton
    Mostly 35mm: http://flickr.com/mdarnton
    You want digital, color, etc?: http://www.flickr.com/photos/stradofear

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