Quote Originally Posted by Fast Glass
I was thinking in terms of shooting birds with 400mm with a feeder, you can forget about wild birds with the 100-400mm!

Ah, yes...because these two are quite domesticated. [:P] The yellow warbler is cropped only to convert from landscape to portrait, and the GBH is not cropped at all (both withEOS 7D and EF 100-400mm f/4.5-5.6<span style="color: #ff0000;"]L IS USM @ 400mm):