A typical building entry.  This one is a suburban office park.

Birds will attempt to fly through these windows.

Some these trees are on the other side of the building; some are reflections. 

Birds will try for all of them.

This building is on the  Northwestern University campus in Evanston.

This could be a window in a residence: a clear line of sight in one window and out another.

Look at how far away the reflected trees are --across a large yard-- yet they are very vivid.

This is a golf course clubhouse - with the see-through windows on all sides.