The 450mm equivalent of the long end of my 70-300 is just barely enough if the bird is nearby. 71mm is wider than the wide end (35mm equivalent) and far too wid

The 450mm equivalent of the long end of my 70-300 is just barely enough if the bird is nearby. 71mm is wider than the wide end (35mm equivalent) and far too wide for anything that'll run/fly away if I get close enough.