Originally Posted by
DullesJason
What??? f/5.6???
Seriously though, if I wanted that kind of reach, I'd prefer to save $90k, buy a nice Porsche Carrera 4 with the savings instead . . . . and then spend a much more sane $10,000 to get a 600mm f/4 and TC for 1200mm reach at f/8. No biggie, esp since it has VR/IS. I'm a Nikon shooter, but I bet Canon has something similar, so here's what I'd get:
http://www.kenrockwell.com/nikon/600mm-vr.htm
And you could drive the Porsche to get closer to the subject so that you would not need such a long lens.