experience with a 2x TC on 70-200f/4 L

Anybody ever tried that or is best to stay with a 1.4 teleconverter

Opinions.

many will say it's best to stick with a 1.4x TC

the 70-200 very happily accepts a 1.4x TC --- IQ is still superb and you have the ability to AF, and only lose 1 stop of light --- with the 2x TC you lose 2 stops of light AND the ability to AF, and 2x TCs tend to reduce IQ much more than a 1.4x TC

I have. Which is why I got the 100-400 .

That is the short version.

Although IQ isn't even all that bad, you do lose AF on most bodies, which was to me the most limiting factor, especially as I tried to follow fast and low flying planes with it. And don't even think of shooting in overcast or stormy conditions; contrast just goes down the drain very, very rapidly.

In a bind, it is a solution, but certainly not for regular use, IMO, unless you have sunny conditions and plenty of time for the shot.

So, I do think it is best to stay with a 1.4X tcon, with the F/4 version.

Kind regards, Wim

I have both. I do use the 1.4 a little more. But the 2X is nice to have for those special moments. Manual focus is not a problem for those that took pictures before auto-focus came out.

I posted some images on this thread. Not as bad as I expected, but the 1.4x is much better...

I tested the 70-200L-f4 + 2xII on my 1D the last time someone asked the question.
AF and IQ were much better than expected.
No AF on the 5D.