Well I've always been looking for the holy grail looking for great IQ in a lightweight system, and hence why I have two systems at present (Nikon FF and Olympus M4/3). I have always been happy with both, but in an ideal world I've always wanted one system.
Now that Sony has brought out the A7RIV and finally improved the ergonomics to a point that I can actually use their bodies, and has the crazy 60mp sensor that allows me to get 2 x crops with 15mp it does appear that I can have the best of both worlds. I can buy the Sony 100-400mm and crop 2 x to give me the same FOV as my 100-400mm on the Olympus, albeit with a slight weight penalty, but still over a kilo lighter than my previous wildlife setup (Nikon D850 with 150-600mm).
Add to this that Sony have opened up their mount to 3rd party (so in theory 3rd party lenses should work just as well as Sony lenses) it opens up the opportunity to a host of lightweight lenses, such as the soon to be released Tamron 70-180mm f2.8 weight in at just 800g, that's the weight of a 70-200mm f4
. There's then 24mm and 35mm primes weighing less than 100g and easily pocketable. It's just a system that makes sense for me right now, and as much as I love Nikon and Olympus they can't offer everything Sony can at the mo.
I've gone back and forth and then back and forth some more, but providing I can get the price that I want for me gear I've decided to make the switch. I'm slightly apprehensive as I've never been the biggest fan of Sony colours, but they have improved from generation to generation and after having downloaded some raw samples I believe that I've come up with a preset to match Nikon (my favourite colours of all systems,....... barring Leica
).