I'm going on a trip to Nepal at the end of the year and intend on taking my 5D mkII with me, with the intent of doing some night-timelapse photography on the Annapurna Circuit.
The time of year I am going can get cold af (sometimes -20c/-4f before wind chill). In the past, cold temperatures ("cold", as in 5c/41f) can often result in dew forming on the lense within an hour or 2 and ruining everything.
My question is; will dew be an issue if the temperature is this low? Using methods of heating the lense will probably be unsuccessful/pointless at these temperatures as its just so cold.
Aside from the issue of dew, are there any other recommendations any of you may have for nightlapse in these temperatures?