Don't do like I did and wait too long. :redface: The first photo is late one afternoon when I decided to check it for dust. I found plenty! I am extremely careful with my equipment and still the sensor was covered. The second photo is the next day after 6 cleanings. Still not completely spotless but better than before. I won't let this happen again. Pointed toward the sky @f/22 and out of focus. Shows the spots better this way.