Re: [APML] Frozen Cameras

[Jerry Lodriguss <jml@astropix.com>]

It may be that the lubricant inside the camera may be freezing preventing 
the shutter from opening.

For working in that kind of cold, you may need to send the cameras off to 
get them winterized where the lubricant is removed.

Alternatively, you could buy some Kendricks anti-dewers and use them on the 
bodies as well as the lenses, and wrap them in some type of insulating 
material after the heaters are on.

I would not advise using hand warmer packs as they release moisture in 
addition to the heat.

Jerry


At 05:25 PM 12/9/2002 -0500, you wrote:
>Friday night, I drove to my dark-sky site for photography.  High on my
>list was getting Orion which never happened the last two years.  After
>a late start on the road, I ended up setting up in the dark, two hours
>later than planned, then found that I had tightened the worm down too
>tight on my CG5 mount so the motor couldn't turn the screw.  I
>corrected that (in the 10°F cold and dark) and finally was ready to
>shoot around midnight.
>
>By that time, almost everything was covered with at least a thin layer
>of frost, and the 60mm guide scope had at least an 1/8" of frost on
>the tube.  I duct-taped hand/toe warmers to lens barrels of my two
>35mm Pentaxes and various other places to keep the frost at bay.  One
>of my YashicaMAT's turned out to be damaged when I found I couldn't
>focus.  I don't think it was the cold that froze it, but I'm not
>sure.  Fortunately, I had it repaired during the summer and it is
>under warrantee, so it is now in the shop for a free repair.
>
>Both Pentaxes *seemed* okay, but today I picked up the film and found
>I had *nothing* on either roll, one LE400 and one Supra 400.  Both had
>been shot at f/3.6.  My second Yashica 12 had two good frames, both of
>Orion at f/3.5 with a Tiffen Fog-1.  I'm trying to figure out why I
>had nothing on the Pentaxes and am suspecting my cable releases froze
>and didn't really trip the shutters.  By the time I called it quits,
>the temperature had dropped to about -5°F.  But I know that for at
>least one of the three exposures I listened and would have sworn that
>I heard the shutters trip.  Even the Yashica 12 which *did* work had
>problems.  I apparently didn't get the shutter cocked for the third
>frame and got nothing for it.  The frame spacing for the two shots I
>did get was quite wide compared to normal daytime shots I've made.
>
>Has anyone had similar experiences when shooting in very cold weather?
>Surely there are some Canadians or other folks living further north
>than I do in New York that have shot in the cold.  What, if anything,
>do you do to keep your equipment warm enough to operate correctly?
>
>I'm happy I ended up with two good frames of Orion, but losing one
>camera and getting only two frames out of nine was a little
>disappointing....
>
>roland
>--
>                        PGP Key ID: 66 BC 3B CD
>Roland B. Roberts, PhD                             RL Enterprises
>roland@rlenter.com                            6818 Madeline Court
>roland@astrofoto.org                           Brooklyn, NY 11220
>
>
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