Last weekend, I tried shooting a wide-angle shot of a sunrise on the beach:
You'll notice that there is a haze/artifact around the sun in an otherwise cloudless sky. What causes this? How can I avoid it?
The image is a bracketed HDR shot (3 images at -2, 0, +2), taken with a Tokina 11-16mm f/2.8. The artifact appears in the original shots as well (most noticeably in the 0 exposure compensation shot).
As requested, here are the original bracketed shots (resized down a lot to limit file size)