Switch to English Language Passer en langue française Omschakelen naar Nederlandse Taal Wechseln Sie zu deutschen Sprache Passa alla lingua italiana
Members: 73,996   Posts: 1,633,331   Online: 1185
      
Page 2 of 2 FirstFirst 12
Results 11 to 12 of 12
  1. #11
    benjiboy's Avatar
    Join Date
    Apr 2005
    Location
    U.K.
    Shooter
    Multi Format
    Posts
    7,699
    At Minus 35C the molecular structure of metals change, metal components became brittle and break in intense cold .
    Ben

  2. #12
    greybeard's Avatar
    Join Date
    Jun 2005
    Location
    Northern California
    Shooter
    Large Format
    Posts
    377
    Images
    6
    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...

Page 2 of 2 FirstFirst 12


 

APUG PARTNERS EQUALLY FUNDING OUR COMMUNITY:



Contact Us  |  Support Us!  |  Advertise  |  Site Terms  |  Archive  —   Search  |  Mobile Device Access  |  RSS  |  Facebook  |  Linkedin