Hi, Just got back from a trip into the Central Plateau region of Tasmania, all 1200m+. We were camped and the nights all went sub zero [C] but probably not below -4C. (the water on the ground was frozen first thing in the morning) The XPro1 was in my daypack and a couple of the nights it sat in the vestibule of my tent, so must have been close to ambient when I took it out to take dawn shots each day. On the days it was left in the vestibule, it took a couple of tries to get it to fire up - when flicking the switch to 'on' it would make a noise from the lens as it normally does on power up, but the VF would remain blank and the camera would not respond to any controls. Turning it off and then on again resulted in a normal usable camera. After the first experience of this, I brought the camera inside the tent at night and it was fine the next morning. I left it in the vestibule one more night to see if the problem was temperature related, and it played up again the following morning. Interested to hear if anyone else has seen this behaviour?