HP5+ fogged by xrays?

Discussion in 'B&W: Film, Paper, Chemistry' started by malinmalin, May 23, 2008.

  1. malinmalin

    malinmalin Member

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    What are the telltale effects on film that has been zapped with too much
    xrays? I have ~10 rolls of HP5+ that went into my checked luggage all
    the way and back from SE Asia a few weeks ago.

    The first roll I finally had time to process this week was not completely exposed
    and the unexposed frames show a lot of uniform, very dense fog all over which
    is also visible between the exposed frames, something that I have never seen
    before using my usual dev recipe.
    Does xray fogging produce 'hot-spots' or is it very uniform?

    Trying to figure out what went wrong...
    jf
     
  2. 2F/2F

    2F/2F Member

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    X-rayed film could have a variety of odd marks, streaks, hot spots, and overall higher level of fog, higher grain...you name it.

    It is not that likely in carry-on bags. But with checked luggage, which uses stronger beams of rays, and a high-speed film like HP5, it is likely you will have some effects from the X-rays.
     
  3. Ian Grant

    Ian Grant Subscriber

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    My HP-5 went through the scanners for hand baggage about 15 times on a trip to Chile & Peru last Oct/Nov with no problems.

    I'd expect problems if it went in the checked baggage in the hold, and all manufacturers warn against carrying that way.

    Ian
     
  4. malinmalin

    malinmalin Member

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    Film went through checked bags, not carry-on.

    Anyways, I'll process more rolls over the weekend and I'll know for sure.
    Just to reiterate: the fog is very uniform all over the frames...


    cheers, jf
     
  5. Neal

    Neal Subscriber

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  6. malinmalin

    malinmalin Member

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    Nope, no one forced me, it was my own stupid idea :smile:
    However I was once denied to have a hand-inspection
    of my carry-on rolls at Heathrow Airport and was forced
    to have them x-rayed/scanned...

    Looking at the Kodak examples gives me hope as
    there is no banding, etc on the neg....

    regards, jf
     
  7. Saganich

    Saganich Subscriber

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    The X-ray will cause more uniform fogging with density variation due to scatter. The luggage scanners for checked bags can ruin film on one pass, if they stop for a second look forgetaboutit, they can focus on particular items in your luggage especially anything electronic looking, once that happens any film in the bag is toast. Even at a low energy like 70KeV the dose to your bag will increase from about 0.2 cGy/sec (rad/sec) at 200cm to 7.0 cGy/sec (rad/sec) at 30 cm, and they get in closer then that. It is likely that your checked luggage will be exposed to greater then 30 cGy/sec (rad/sec) and if they dwell on something in there...well you get the idea.

    The carry on luggage scanner is a weak 70KeV or so X-ray which is attenuated by .5mm lead equivalent sheath. At that X-ray energy and distance the tin of the film will likely attenuate 50% of the exposure anyway which is why you should be careful with 120 roll film. I would expect that without the tin can 120 film may not stand too many passes.
     
  8. eddym

    eddym Member

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    What "tin can"?? :confused: