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  1. #11
    greybeard's Avatar
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    The cold is so intense, a friend held his camera to his face to compose the shot, when he lowered the camera he took a chunk of his nose with it.

    The dryness is also a problem. I found the skin on my fingers dried out and split continuously so that winding on a film was painfully bloody business.


    Josef Stalin is supposed to have once said, in regard to military matters, "Quantity has a quality all it's own". It seems that extreme cold is that way, too---difficult for most of us to relate to.

    One of my father's anecdotes about Manchuria was that the POWs were not required to go out if the temperature was more than twenty below zero (I should have asked whether that was Fahrenheit or Celsius*). The decision was made by tossing water into the air. If it hit the ground as ice, it was too cold to go out!

    Most extreme cold sluggishness seems to affect 60s-70s gear most commonly.

    This may reflect closer mechanical tolerances and greater complexity in gear from that period, alleviated by even better manufacturing and lubricants in contemporary equipment. My ancient Yashica has never been serviced in its life, and still works at all speeds, while every Compur shutter that I have handled was balky at low speeds unless it had been regularly maintained. Complexity, tolerances, and basic design (a press-focus shutter can be a lot more robust than an auto-diaphragm one) all bear on tolerance of low temperatures or simple neglect.

    *if the number had been -40, it wouldn't have mattered!

  2. #12
    benjiboy's Avatar
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    At Minus 35C the molecular structure of metals change, metal components became brittle and break in intense cold .
    Ben

  3. #13
    greybeard's Avatar
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    At Minus 35C the molecular structure of metals change, metal components became brittle and break in intense cold .

    Well, some metals, yes; others, no. Has anyone encountered a camera failure because of this? I'm not trying to be snarky--- I am amazed that in the years since left materials science graduate school it never once occurred to me that camera components like steel pins, gears, and springs could be at risk at sufficiently low temperatures. The frames and cases (if not plastic!) are probably safe, since they tend to be aluminum-based die castings and and don't see a lot of stress anyway. Brass and nonmagnetic stainless steels are also immune, but the hardenable stainlesses (I don't know if they are used in cameras) might not be happy at forty below.

    Anything plastic--including light-seal foam made of anything but silicone--is going to be pretty stiff at that temperature and may not function even if it isn't permanently damaged. Also, metal assemblies held together by structural epoxy can often be disassembled by simply putting them in a food-type deep freeze (typically, only -10 F) until the combination of differential contractions stress and brittleness of the epoxy allows it to simply pop apart. This could definitely be bad news, particularly if the manufacturer didn't test the materials set thoroughly.

    I seem to recall that NASA had trouble with camera lenses in extreme cold, because the outer elements of cemented lenses could expand and contract enough to break the cement bond, if the inner elements were not allowed enough time to follow the temperature change. This is probably not an issue for field photography, but it can be if you are working around things like cryogenic rocket fuels. Even if the lens doesn't fail outright, the stresses and strains probably don't do the optical corrections any good!

    Staying here in sunny California is starting to sound better and better...

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