[MJKoski]

The grip is no joke. KP was with me a whole week in pretty nasty conditions some three years ago and I had to keep it outside continuously. No way it would survive the condensation which a well insulated jacket will instantly cause if kept inside the jacket between exposures. The grip is solid when attached properly and provides a backup shutter trigger. Yes, the main shutter trigger of KP is the one which may fail before the photographer in extreme cold.



There it is, KP after a long day outside. We stopped as our camera could not be operated any longer. They were covered in hoarfrost, none of the dials could be turned and no buttons responded to presses. Lenses and filters had a thin veil of frost which messed up the photos (no contrast). Well, cellphones worked in some way although it was not possible to recharge them.

Windchill effect was such that -30C temp felt like -50C after the sun went down. It is the wind which makes the hoarfrost to stick in cold and humid conditions.

[mikesbike]

Wind chill causes heat to dissipate faster. The furnace thermostat keeps house temps to the point that has been set, but is somewhat less accurate and responsive if winds are high in cold weather. The setting will often need be higher for the same degree of comfort, the furnace must work more, and the cost will be higher. Stands to reason this heat dissipation will also affect a battery in a camera as well. As MJKoski says and shows, the battery grip supplies more power and more insulation.

[pentasonic49]

The camera will be at the same temperature as a thermometer sitting beside it and wind has nothing to do with it. Windchill is calculated from temperature and wind speed. Your skin will loose heat at a certain rate in still air conditions as there will be a temperature gradient between the skin and a small distance above that skin. As the air starts to move, the temperature gradient gets steeper as the thin layer of cooling air gets blown away. The higher the wind speed the quicker the heat is removed, and you feel colder even though the thermometer reads the same.
If you look in your cameras manual, it should list the minimum temperature that it will function at.

[leekil]

What I noticed was that when carried on the windward side (out bound trek), the battery acted like it was many degrees colder with some power glitches. When carrried on the leeward side (return trek) I had none.

Where was the sun? That can warm the camera up significantly; if it was shining directly on it on the return trip, but not outbound, that could be the difference.

[jgnfld]

Where was the sun? That can warm the camera up significantly; if it was shining directly on it on the return trip, but not outbound, that could be the difference.

At 3 the sun bearing was 220 degrees 10 degrees up. At 4 the bearing was 232 degrees and 2 degrees up. The trail outbound is close to 180 true and 0 returning. With all the microfronts, sun/cloud conditions were fairly equivalent each way except that temps fell 2C over those the 2:30-4:30 time period.

I was simply surprised. I have a lot of experience shooting in the cold (like a bit south of Intl Falls, Mn where my family used to have a cabin and it once hit -51F*) and have the equipment to go lower but wasn't carrying it. As I said I haven't conducted a true experiment on the matter, but this seemed liked an indicative natural experiment showing something I hadn't noticed before.

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*Did you know that -50F vodka poured (well slithered like glycerin) into a glass of room temp mix makes an instant daiquiri?!!!

[MikeMcE]

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*Did you know that -50F vodka poured (well slithered like glycerin) into a glass of room temp mix makes an instant daiquiri?!!!

Now that IS news.

Not sure I could hold it as my fingers have long since frozen and fell off!


Hang up and DRIVE!

[jbinpg]

Just an aside on windchill. I was working for Environment Canada's weather service in the 1980s when the meteorologists decided they wanted to educate the public on windchill. They came up with a new chart displaying windchill in a more scientifically appropriate watts/sq meter instead of the often misleading equivalent temperature. After trying for a year or so with the new uniits, they realized that the public just wasn't having anything to do with the new units so they scrapped it and went back to equivalent temperature. This prompted the trilateral meeting of the USA, Canada and the UK in year 2000 that signed on to a new official definition for windchill using equivalent temperature.

[TwoUptons]

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*Did you know that -50F vodka poured (well slithered like glycerin) into a glass of room temp mix makes an instant daiquiri?!!!

When I was growing up, my grandmother had a range of drink mixes that came as little packets of powder.
I was really wondering for about three seconds how in the world that would work...

I expect the wind could have an effect on the cooling of the camera, in the same way a car radiator fan improves its heat exchange.

In "normal weather" (sure, fine, laugh all you Canadians, but it was 23 C at my house today, even if it was a dreary mess), the impact is negligible, as the battery capability doesn't change much at those temperatures.

But when the camera gets close to its published limits (-10C for the KP?), I'm just going to guess that the tests were done in a still air room, so battery and circuit capability included whatever heat was generated by the camera working, undisturbed by wind. In that case the extra heat really helps, as the battery (and who knows what else) are close to their limits. Add a little "reality", and some of that heat is blown away, and the battery/camera temperature internally drops from, say -8C in a windless -10C room to -10C when it's -10C and windy outside.

It isn't the same mechanism entirely as wind chill (the camera won't 'feel' colder than the actual surrounding temperature), but it's increasing heat transfer out of the system, making the system colder for a given outdoor temperature...

-Eric

[c.a.m]

In "normal weather" (sure, fine, laugh all you Canadians, but it was 23 C at my house today, even if it was a dreary mess)

Whaaat? Who's laughing? We're too busy preparing some snow to send your way.

Payback for the occasional nasty Colorado Low that makes it up to Ontario. Thanks y'all.

- Craig

[jgnfld]

Starting to work on my panos. KP certainly didn't mind the weather IQ-wise. Pretty easy to see the lighting that got me out there!

4 shots knitted with Hugin.



A much higher res version is available here: http://www.nfgarland.ca/RobinHoodPano.jpg

55-300 PLM at 55. I took a bunch more and am working on them but switched to the 16-85 at about the same FL. May post some in a bit if they look good to anyone.

xposted to "bad weather" "best kp shots"

[SSGGeezer]

Wind does nothing but as I have noted before many times, the standard KP battery is your enemy in the cold. Get the grip and D-LI90 (original) to solve all power glitches in the cold.

^^^^^^^^^This!^^^^^^^^^^
Wind chill only affects warm blooded furless critters....Humans specifically. Get the grip. I have shot my KP and my old K-50 in -25C weather with no problems. Geeet the grip and an actual Pentax LI90 and have no worries.

[noblepa]

I would have loved to have joined you on that trek. Cape Spear -- one of Canada's greatest locations, IMO. Even in that harsh Newfoundland weather!
"Wind chill" doesn't apply to inanimate objects such as cameras.
- Craig

I'm not sure that is entirely true.

Wind chill, as I understand it, is really a rate of heat loss. That means that a warm object will lose heat faster, but will not get colder than the ambient temperature.

IOW, if an object (with no internal heat source) at 70 degrees (F) is placed in an environment where the ambient temperature is 40 degrees, the object will eventually drop to that temperature. The amount of time this takes is dependent on several factors, including the mass of the object and its surface area. Let's say it takes this particular object 20 minutes to drop from 70 degrees to 40 in still air. If there is a breeze blowing, it will lose heat faster, perhaps in 15 minutes. But it will not go below the 40 degree ambient temperature.

Batteries are chemical devices. All battery technologies that I know of provide less amperage at cooler temperatures than at higher ones. So, the battery in you camera will produce less current and may fail sooner in cold weather than in warm. Wind chill might make it reach that point a little sooner, but it is the actual ambient temperature that is the culprit.

The mechanical parts of your camera, such as the shutter and mirror mechanisms may suffer as well. Again, it is the ambient temperature, rather than the wind chill that is the problem. Parts, especially of different materials, may contract due to the cold, at different rates. Tolerances that are perfectly fine in warm temperatures may suddenly be too tight or too loose, causing binding between moving parts.

Lubricants may harden, as well, restricting the free movement of parts.

All that being said, I think that the battery issues are the most relevant to real life. I've never heard of a camera binding up because of cold, but I have heard of batteries failing due to cold.

Back in the film ear, some cameras, notably the Pentax SF1, had an option of a remote battery. You replaced the in-camera battery with an adapter that had a wire to a battery pack that you could put inside your coat or in a pocket. This kept the battery warm and minimized the current or voltage drop.

[stevebrot]

Does "wind chill" and/or possibly humidity issues as well actually MEAN anything to a KP and it's battery

No, not in the sense of reported wind chill, but the camera will lose heat by convection and convection exchange increases with air movement. As noted above, your first lines of defense are a strong power source and tempering heat loss by using a heater and/or insulation.


Steve

[mikesbike]

If you look in your cameras manual, it should list the minimum temperature that it will function at.

This is correct. If you face conditions below that temp, wind chill will be a factor in the camera losing heat faster after leaving any heated environment, or after being removed from a carrier providing additional insulation. Added insulation will prolong the loss of heat. Using the larger battery might also be a factor, since the spec for the KP's operating temperature is based on its standard battery, among other aspects.

[MJKoski]

Cameras easily become stuck in the cold. They stay there on tripod while moisture of air from breathing then forms a layer or frost on the backside of the device. It makes everything frozen solid if hoarfrost doesn't.