It really depends on the relative humidity when it comes to fogging, was in Beijing, roamed around early in the morning at around 5AM, temperature was down to about -4, but it was so dry, at around 20% humidity, as dry as the dry box we use...so no fogging at all. Spare batteries is a must. On the other hand, had fogging problem in chiangmai, and shanghai where it was closer to 8 and 4 min respectively. My G3 with microdrive (card error) played me out and batteries ran out of juice very often.