Upload & Sell: Off
For those of you with a 1D-series body that focuses at f/8, do you have experience with the 100-400 and a 1.4x extender? Specifically, how is the AF for tracking moving objects (sports, birds...)? Even more specifically, compared to a 7D with the bare lens (no teleconverter)?
I ask because I am contemplating getting a 5DIII, but might need to sell my 7D and various lenses to fund it. The premise of my question is that the 5DIII, when the new firmware comes out, will hopefully do as well at f/8 as prior bodies. Using the 1.4x extender would essentially restore the pixels-per-duck that the 7D can achieve w/out an extender. I suppose there is the risk that the f/8 AF will only work decently for particular lens/TC combinations - presumably the latest super-teles with latest extenders will be the best supported.
And - the 5DIII would be an all-purpose camera for me. Telephoto capability is just one aspect of performance I am considering (so in other words, I already understand that if I ONLY wanted to shoot long, that the 5DIII w/teleconverter might not be my first choice).
Anyhow, any insight that anyone can shed will be appreciated.
Note: I am posting another related question about the 70-200 II under a different topic.