Hi all,
A few weeks ago, I took my first outdoor shots with my 20D (purchased mid-December). I was using a new EF-S 10-22mm and noticed that my shots had ghostly grey blotches and specs in certain areas. Since I had never seen these on shots with 50mm, I figured it was on the lens. My dealer (Henry's in Ottawa) suggested I bring the lens in and they'd check the rear element for dirt.
However, this past w/e, I took both lenses outside in bright sun and took a ton of shots. Low and behold, the spots were visible with both lenses, but only at apertures of f/11 or smaller (at f/22, they're clearly defined and large). Larger than that and they are invisible, which is why I had never seen them during the previous weeks of indoor, low-light shooting. The spots always appear in the same areas so I'm pretty sure the sensor is dirty.
Has anyone tried cleaning their 20D's sensor? Have you been successful? Has anyone had to send their camera to Canon? What was the outcome? Could it be that this contamination has been there since day 1 -- I'm very careful about keeping the body protected during lens changes and I've barely used the camera outside.
Thanks!