« on: January 23, 2011, 11:42:28 AM »
I'm sure everyone would love to have a 400mm f/2.8, but if you take a look at the cost you'll see why more people use the 100-400 despite the slow 5.6 on the long end
While cost of the 2.8 is too high, last year I bought a 600mm f/4 used. Carrying it around and setting up with heavy tripod and wimberly was just too much, it took up a lot of space in my car too, so I sold it and kept using the 100-400mm L.
For my use, portability has a higher priority than larger aperture. I have considered the 400mm DO, but it is also pretty high priced, and is not much sharper than my 100-400mm, and the background is not smooth like the zoom.