So a summary of my day out:
Temperature turned out to be -20C. I went out at 07:55. Beautiful sunrise, and clear skies.
Clothing
Feet: wool sox and leather boots.
Lower body: wool boxershorts, wool pants and windproof ski pants
Upper body: cotton perforated "wife beater", thin wool shirt, thick wool sweather and thick parkas
Hands: leather gloves with wool lining
Head: Buff headnecker and russian style faux fur hat
The hands were the only problem of the day. Obviously, to handle a camera you need fingers, so mittens were not an option for me. I am lucky that my parkas has fleece lined outer pockets, that helped warm my fingers, but I had severe spells of "nail bursts" during the trip. It was expeced though, as I suffered frostbite during my army service on my fingers and my earbuds - those are always the areas that get hit first, when winter kicks in.
Lower and upper body felt perfect for the entire walk - dressing in layers is key: keep the wind out, and put three or four layers on the upper body and you'll be fine, even in -30C.
I did use cold weather cream on my face before going out, as the cheeks and nose are unprotected from the chill - glad I did. The
Buff really was handy in keeping my breath from fogging the viewfinder. Kept me warm also. Buy it, if you don't have one.
Equipment:
Took the K-5 with the FA43, 0.6 and 0.9 ND filters, a polarizer, my
Domke F-3X and the
Gorillapod.
The K-5 performed without issues. Obviously the viewfinder will fog a little and the LCD will be slower in -20C, but the camera functions flawlessly. Upon my return I left in in the Domke bag on the bedroom floor, and then took the bag out in the living room after a few hours. A quick function test this aftenoon turned out as expected: no issues.
The Domke F-3X is my favorite bag because of it's compactness and ability to hold more than expected. Today it was almost empty, but I was still glad I brought a bag (I don't use a neck strap, but a leather grip, and holding the camera in my hands for the entire walk would have left my fingers so cold I would have cried).
Forget the Gorillapod in low temperatures: the joints of the legs gets mushy, and will fail you. Also, the ballhead became hard to manipulate as it froze (propably true for all other ballheads as well). I regret not bringing a "proper" tripod, even if the weight would have been greater.
Shooting
I tried using ND filters to capture smoke and frost. The remote did not work (propably user error), and since the Gorillapod did not handle the cold, most of my shots on bulb got ruined. I used Live view for many of the shots, which worked well, even if the LCD got slow. It is impossible to avoid some fogging of the viewfinder in these temperatures, but using the Buff helped a lot - I had no real problems using the viewfinder for my walk.
I turned off SR before going out, which turned out to be a mistake. The cold and the stress that follows ("get the shot off before your fingers fall off") made many of my shots turn out unsharp due to camera shake.
Conclusion
All in all, a fun day. As always I went out optimistic, thinking that this would be the day I turned in to Robert Kapa, but, alas, I came back with the usual mediocre set of shots. Still, I had fun, and I also learned a few things. I'd like to thank everyone who contributed in the thread for their helpful insights, and I hope you enjoyed your World Pentax Day - wherever you are.
Here are my two keepers from the day: