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Lazybones
18-Jan-2007, 23:38
Hello people!

It's been cold here in Minnesota lately, but the photoging must go on. At what temperatures would one become concerned about damaging a lens/shutter?

I am aware of the Kodak Tech Pub about Arctic Conditions. We're talking temps in the teens to twenties (Fahrenheit).

Thanks!

-LB

David R Munson
19-Jan-2007, 00:13
The only cold-related difficulties I've ever run into has been batteries crapping out due to cold. When it's well below zero, I've had leaf shutters get sluggish, but even then I doubt you're really doing any damage to the shutter.

John Kasaian
19-Jan-2007, 00:37
I was told to remove all the lubricants and relube with K-Y jelly. No, really! :o

Walter Calahan
19-Jan-2007, 07:31
John, it will never get that cold to use K-Y jelly. Grin.

Temps in the teens and twenties is not a problem for modern shutters.

tim atherton
19-Jan-2007, 08:51
I've used both older and more modern lenses down to -35c to -40c - never worried about or experienced damage to lens or shutter. Some get sluggish and slow due to the lubrication thickening up. Not long after that I usually start to freeze up...

David A. Goldfarb
19-Jan-2007, 09:36
If the shutter is old and hasn't been cleaned for years, it can jam up in the cold and not necessarily come back when it's warm, but if things are generally in good repair, you should be okay. Happened to a 35mm folder with a leaf shutter I had.

Big changes in temperature might worsen existing lens separation. I think I've seen that happen once.

Lazybones
19-Jan-2007, 13:29
Thanks for the information. I can now rest easy.

Tom Coverdale
19-Jan-2007, 19:23
Just for info....I have used modern shutters here in Wyoming at temperatures approaching -15 F with no problems other than working the controls with gloves on.

Dave_B
19-Jan-2007, 19:51
LB:
I have built complex optical systems for a living. IMHO, the main issue is not so much the absolute temperature but the changes and rates of change in the temperature. Things like glasses and metals have very different amounts of thermal contraction and also very different thermal conductivities. This means that lens systems that are warm and then taken into cold environments or cold and then taken into warm environments can experience a lot of mechanical stress while they come into thermal equilibrium. Also, condensation can put a lot of water onto the surface of a lens that is not good for it or the AR coatings. The main precaution is to take it easy and allow the lens to cool down or warm up slowly. Thermal shock is not good for any optical system.
Cheers,
Dave B.

David Karp
19-Jan-2007, 20:41
Frank Hurley took some pretty awesome LF photos in a pretty cold environment (Antartica). I have not read of any problems with his lenses/shutters. He also used some small format cameras that I assume had leaf shutters. Again, no mention of problems. Interesting question.