It basically looks like a big white circle (much larger than the sun), but oddly has a small black circle on the inside. This black cirlce is probably about the size of the actual sun. Here is a rendition:



So I have a question for anyone that knows the physics of lenses and/or photography. What is this black cirlce in the middle?

I've seen other pictures of the sun taken on good cameras (as opposed to my crappy cell phone camera) and they look similar except on good cameras there is no black circle in the center.