So I've noticed some splotches here and there on some of the shots I've taken and today was the worst. Grey and overcast with bright diffuse light, shooting up at the sky. I have a sequence of shots that clearly demonstrates the dirt, and also proves it to be inside the lens.
First, at F10. You can see a couple of blobs, one 45 deg down from the tail and one 30 deg up.
Now, at F18. Same blobs, only a bit more resolved now. One straight down from the tail, one at 30 deg up and left.
Now, finally, at F32. Well defined dust specks.
So, they are in the lens, somewhere in front of the aperature, but not on the front element or protective filter. Unfortunately, a lot of the shooting I do is with the sky as a background for most of the shot and they are pretty noticable all the way down to the F6-F8 range with the sky as a background. Any suggestions? Obviously I can send it to Nikon to be cleaned, but I'm curious if anyone has other suggestions.