In really cold weather, a few of the most popular ordinary digital cameras can be made to mimic expensive CCD cameras. At warm temperatures (anything comfortable to human beings) they develop noise quickly for exposures of more than a second or two. See the October and November 2002 issues of Sky & Telescope. Some of the images from digital cameras rival anything done with any other technology, but only when it's nasty cold out. Having worked long and hard on some photos, I am just floored to see my best efforts matched or exceeded by a digital camera--see the Orion photo on page 128 of the November issue, for example.