The fact that the shooter is in the picture is immaterial.
Notice the greater intensity inside the ring as compared to outside.
This mean *SOME* type of light gathering device. What kind?
A Lense? Nah, to obvious, but still a refracting lense might work.
A Prism? Nah.
A Mirror? Maybe.
A Highly polished something? Maybe.
Some kind of Communications Dish? Maybe.
Lead Crystal? Hmmm. That would also give that order of color at the edges.
The Shadows lineup in the circle and outside the circle. Mean something like Noon or the time they are lined up.
This is my guess:
How abouta mirror that reflectsthe Noon Sun through a Lead Glass Decorative Window (acting as a refracting lense of sorts), High atop a Building?