My 20d has an unusual amount of noise, even at ISO 100. Here is a pic from my 20d: Here is a similar pic from my roommate's 350d using similar settings: With the 350d, the background is blurry but not noisy. The picture taken with the 20d, the background and upper left of the chair is very noisy. I reset the camera to all factory settings. What am I doing wrong here? The lens I'm using is a Canon 28-135mm f/3.5-5.6 IS USM with a 72mm Hoya UV filter.