I captured this Chickadee this weekend through the kitchen window. It was raining outside and most of the birds were just hanging out. The glass in the window seems to have affected the sharpness and IQ but still pretty darn good.
Captured with Canon 7D and Canon 400mm 5.6 L handheld – through the kitchen window.
EXIF: 1/100 sec, f/8.0, ISO1000, 400mm, +1/3 EV