John A , Feb 02, 2010; 01:13 p.m.
I had some issues with my camera and it took about 3 cleanings with the eclipse fluid and swabs to get rid of them. If you have the ring issue, I wonder if you are getting mirror oil flying around in there--apparently an issue with some 1dsmkIII's. The rocket blower can also create issues if not kept securely in a baggy to keep the dust out--ends up ballistically putting dust onto the sensor!
Anyway, I fixed my seemingly welded on spots by cleaning, blowing and cleaning 3 times before they were gone--takes some patience.