I just upgraded to an a7RIV and would like to hear opinions on lenses. In your experience what are the the pros and cons of using an SEL70200GM with 1.4x (or2x) teleconverter vs using an SEL100400GM? Your thoughts...
Both very good lenses I have both and the TC I have found the 100-400mm a very versatile lens near macro to wildlife suppose it all depends on what you intend to shoot the 70-200mm is quite a heavy lens oh decisions -decisions good luck whatever you choose.
I've only tried the 70-200 GM + 2x on my a9 so can't comment on the a7R IV I'm afraid. With the a9 it works well but the AF is a little slower and sharpness drops off a bit.
Here's one shot with the a9 + 70-200 GM + 2x @ 400mm, f/5.6, 1/2000, ISO 125.
I might consider doing a bit more of a comparison between the 70-200 F2.0 + 2x and the 100-400. I just have another couple of comparisons that I'd like to do first.
I'd probably lean towards the 100-400 if you think you'll be shooting more at the long end. If you really need the shorter focal length and f/2.8 aperture of the 70-200 then you don't have much choice.
Or you could go with the Tamron 70-180 F2.8 and Sigma 100-400 for less than either of the Sony lenses cost. I've not been impressed by the AF performance of the Sigma though unless your subject isn't moving too quickly.