I shot this as a dust check. D70, w/ 50mm 1.8 stopped all the way down to f/22. Picture is of a blue sky that I then manipulated and pumped up the contrast to make the dust spots more visible. That process also amplified the bright spot in the center which I could already see as shot. Any idea what it is? Is it because I stopped the lens all the way down? Thanks in advance. I can't seem to get the image to post at all. One of those days!