How good is the camera for super long exposures?
All digital camera have the hot pixel problem. Most DSRL camera, when you take a long exposure, take a second picture of the time length without opening the shutter, then subtract the hot spots on the second from the first, as they generally happen in the same place.
The digital rebel does not do this. They have an system that removed the host spots on the fly, and the results look good, but I have only seen up to a 30 second exposure.
I'm wondering if the Digital Rebel's hot spot reduction system would produce acceptable results for 15 minute exposures one would get if they were "painting with light" or couple hour exposures like with star trail photography.