So I was snapping some pics today and when I put them on the computer, I noticed these specs in some of the images. So I entered the "sensor clean" mode on my cam (20D) and looked at the sensor. Sure enough there's specs of dusts on the sensor. I tried using my air bulb blower thingy but to no avail. I'm scared to use the brush...as to I'm not sure how sensitive the sensor really is. Any advice? Thanks in advance.