Re: Sensor dirty?? Yes thats dirt, you can clean the senser, as you do your own editing I think you might as well remove the marks then as its not that bad,
Martin
--- One to one workshop in monochrome, from capture to fine art print, printing service available
Re: Sensor dirty?? A couple blasts of air from a good hand pump might do the trick. I use the "rocket" blower often and it takes care of most dust and such. Don't use compressed air though.
I get tired of cloning these things out, or I miss one and have to go back. Try an air blower...