Here is a simple way to create the illusion of a solar eclipse:
1.First, make a 500x500px backround and fill it back.
2. In the center: put a lens flare 150 brightness with a 105mm prime lens.
3. Then, select the circular marquee and while holding shift to make a perfect circle, put it around the bright area. Then fill the circle with black.
4. Then lastly, use a white paintbrush on the upper left part of the circle to make a Diamond ring effect.
When you're finished, it should look something like this:

More PS works:
