I usually shoot in the f2.8 to f8 range so I haven't seen any signs of a dirty sensor on my D7000. However, I rented my camera to another shooter who shot in the f18 - f22 range and I was shocked to see so many spots on my sensor. It looked exactly like the oil splatter pattern that some have found on the D600. The easy methods of cleaning did nothing.But I really didn't expect the blower and internal sensor cleaning to do much. What I could see were obviously oil spots. I decided to take the bull by the horns and do it myself. I ordered Photographic Solutions Sensor Swabs from B&H for DX sensors. They were only $13.99 plus S&H for 4 pre-moistened swabs. After I received them, It took me an extra day to work up the nerve to use them. This morning, I carefully read the simple instructions several times and went for it. The first swab was a big improvement but I could still see some slight oil smears on the right edge of the sensor. I tried another swab but this time I went top to bottom just on the right edge and it worked perfectly. My sensor looks beautiful now. It wasn't nearly as difficult as I expected. If you have an oily sensor, be careful but try it.
