I took some astro-photos on Sat-Sun night, and then these "winter wonderland" pictures on Sunday morning. -15 C is not cold or unpleasant if you dress well and keep moving and generating heat. If you stand still or the wind is blowing then anything colder than -10 C is miserable. Shot with the 17-40/4L and a circular-polarizer(*) (from Dealextreme), which produces very nice deep blue skyes, and a gradient in the wider shots from almost white to dark blue. Something to practice with more in the future.
Astrophotos will appear when I have time to process them. Also stay tuned for "yellow submarine" fresh out of the mould!
Nerdy Physics Note:
(*) There's no such thing as a "circular-polarizer", in the sense that a single optical element would only pass circularly polarized light (AFAIK), and what they sell in stores as "circular-polarizers" should of course be called a "linear polarizer followed by a quarter-wave plate", but I guess "circular-polarizer" is just shorter and easier. The quarter-wave plate is there because the autofocus system on many cameras uses polarizing beam-splitters for different paths of the beam, so a simple linear polarizer would sometimes cause the autofocus to fail.
now also on Picasa:
http://picasaweb.google.com/anders.e.e.wallin/WinterWonderland#