Taking pictures of swallows flying is a challenging and usually disappointing endeavor because they fly so fast while swerving and dipping and climbing and zigging and zagging that it is extremely difficult to get a sharp picture. However, on this day, I noticed tree swallows going in and out of a hole in a road sign. So I set up my tripod with the big lens at close focus distance and focused on the spot where they would hover before going into the hole, and waited until Swallows came into the prefocused spot, and this is the best shot!