Faced with a nice sky on a dark clear night but feeling tired after a poor previous night sleep and not wanting to set up a tracking mount, I decided to try using Astrotrace to take some shots from a fixed tripod. Astrotrace uses the camera GPS to tell the camera where it is pointing and where it is geographically located. The camera processor then uses small movements of the image stabilizer, to shift the sensor to minimize the effects of the Earths rotation visible in the sky. No system like this can rotate the image perfectly around the celestial poles. It simply minimizes movement across the whole frame. In the attached image, you can just see some movement at the lower right corner of the frame but the rest of the image is not bad. in the larger version, the trailing lower right is easier to make out.
Larger version top of this page :
http://joe-cali.com/astronomy/astrophotography-2/
Joe