Barn Swallow in flight

I'm still trying to find a way to photograph or video the spectacle of hundreds of thousands of Barn Swallows going down into the cornfield to roost for the night. The size of the flock, the darkness of the sky, and the distance to their chosen roost site all conspire to make it very challenging. Anyway, at the same time my mind is being "boggled" by the numbers, I enjoy the close encounters with the individuals who are zooming just overhead as they catch a few more bugs in the fading light.