I was concerned about what might happen to the image sensor on my camera in very cold weather and if it would change the quality of the recorded image, so I posed the question on one of the photography forums that I follow. The consensus is that cold does not negatively affect digital image sensors. However, the cold will cause camera batteries to lose their charge sooner, and the cold metal of the camera on cold fingers or your face while taking pictures could increase the risk of frost bite. In cold weather there are often heat-waves coming up from the ground that will slightly distort things in the distance, causing pictures of distant objects taken with a telephoto lens to be unsharp.
Another real concern is condensation that may form on or inside the camera or lens when bringing it in the house (or into a warm car) from the cold outside, just like it does on my glasses. Condensation forming inside the lens or camera could ruin it and cause all kinds of mechanical, electrical or optical problems. Before I bring my cold camera in the house I will either zip it tightly inside my camera bag or I will put it inside a "dry bag" used for keeping things dry while canoeing or kayaking and seal it up tightly (a large sealed zip-lock bag may work also). First wrapping a towel around the camera may also prevent any moisture that may form inside the plastic bag from dripping on the camera. Then, when I bring it inside I will wait several hours to let everything gradually warm up to room temperature before opening the bag. I guess I can't be in too much of a hurry to get to the photos that I just took or to recharge the batteries. Surprisingly, the same thing happens in the summer when taking a camera from the hot-humid outside in to a cold air-conditioned building. So the same steps should be taken to stabilize the temperature before exposing the camera to the colder room to avoid condensation. Well, that is my photo-tip for the day. Here are a few more photos that I took yesterday (click an image to see them larger).