Okay so my primary business is wedding photography and I have a bunch of great lenses but my hobby is nature photography. I have a Canon 70-200mm 2.8 lens. I was thinking about getting a lense with a greater reach... mainly for bird photography. The wide aperture would not be as important since low lighting wouldn't be an issue. I was thinking about getting a lens extender. Is this a good idea or am I better off just buying a new lens? What has been your experience with lens extenders?