David Arbogast wrote in post #18811029
My 2019 priorities, by far, are more about AF lenses.
My daytrip yesterday had a two-fold purpose: 1. get some landscape photography, and 2. evaluate my interest in wildlife photography. I’ve been waffling about getting into a little wildlife for years, but it’s starting to make more and more sense to me. There are some decent wildlife opportunities near me, and some great ones along the Florida panhandle. Seems like a lot of retirees get into the birds.
My next two lenses most likely to be 24GM and 100-400GM and, if I really want to shoot wildlife, going to need a new body for it because the a7R II is a turd for action.
I rented the 100-400GM to go on my A7iii along with the 2x convertor to shoot planes at an airshow of old planes down here in NZ.
I wish I'd tried the 1.4 convertor. It was fantastic with the 2x, but I think the 1.4 would have been plenty enough. The A7iii can AF at f11 with the 2x and was amazing, so was able to shoot at 800mm.
The biggest problem I had was that as the planes flew by, the tracking was just so good that I would be shooting 35 frames panning with the aircraft each pass they did. 99% of these were in perfect focus, so editing became more about culling from just over 2000 shots I took that morning 
Would love to buy the 100-400, but doesn't come into my budget unfortunately
Sony A7mkiii / Zeiss Batis 18mm f2.8 / Zeiss FE35 f2.8 / EF24-105F4L / EF70-200f4L / EF50mm f1.8 / Sigma 105mm f2.8 macro