Ok, after some advice please for my new toy which I collected today.
Ignoring the extra reach of the 100-400 is that a better option to use on a 1Div than a 70-200Lf4is with a 1.4x extender on?? I have both lenses already, hence the question. I realise that a 70-200f2.8mk2 would be better with the 1.4 extender
Many thanks in advance