The simple answer to this is the following video. I had my Canon 24-105mm f/5 zoom fitted to the Sony A7r II via a Metabones Smart Adapter (With AF). The adapter also allows the lens IS to take over the stabilisation, turning the internal IBIS off. Since Sony don't make (nor will probably ever make) a lens this useful and the fact that the Canon lens IS gives more stable results than the very overrated IBIS anyway, this is very useful for me. These days I'm actually shooting more video than stills, due to my wish to build up my portfolio of stock video clips with several libraries. My Canon 5Ds doesn't shoot 4K video, the Sony A7r II does. So after buying a couple of 128GB Ultimate SDXC UHS Ultra High Speed Class 3 Memory Cards (since the A7r II won't record 4K without cards this fast) I shot these hand held 4K stock video clips of the rain forest that is currently my garden. No other camera will let me do this AND shoot big high-resolution (42.5MP) stills as well.
So despite battery issues, which I'm hoping to solve with an external power pack and the fact I'm underwhelmed by Sony's design, ergonomics and construction, this is a unique camera and suits what I'm doing in terms of output more than any other on the market. In the main I shall be using it as a companion camera to my Canon 5Ds, since I will be using Canon lenses on it almost exclusively. Any idea that I might get the Sony 24-70mm f/2.8 went out the window once I fitted the 24-105mm to the camera. Immediately looking through the viewfinder I could see that the video image was significantly less shaky than using the internal 5-axis stabilisation. Since I want to shoot most of my video clips hand held this is very important to me.
The other feature I like is that the A7r II doesn't 'crop' my 4K frame. In fact when I'm shooting I take what stills I want, then simply press the video button and the 16:9 crop appears and away I go. It's simple, it's quick and the quality is great. And a wide-angle is still a wide-angle.
So for the last few weeks I've been pondering this decision. A lot of stuff has been sold and a lot more is going as well. Because despite my reservations about the professional durability of the Sony FE systems and the (to me) crazy way that Sony operate, this is a camera that I think I can make work for me.
Now I describe Sony's behaviour as crazy because they could (should?) have demolished Nikon and Canon by now in the professional world. But since they really don't seem to know who they are aiming their products at AND the fact that they overprice everything AND the fact that they don't seem to have a coherent and planned lens strategy, they haven't. In terms of quality output for stills and video the A7r II is a remarkable camera. The stills are the best I've seen and the video is pretty nifty too. But all of this comes in a bridge camera package, with the most ridiculous battery life I've ever seen in a high end camera. Yesterday, testing it out, I shot 7 x 20 second HD video clips and 50 stills (raw and jpg.) and a fully charged battery was down to 34%. I wasn't even using AF as I had a Nikon MF lens on the camera. Now this is simply ridiculous. I mentioned before about USB power packs which have more than enough capacity for a days 'normal' use for me. So why on earth haven't sony put one of these in a battery grip for professional users or anyone who wants to shoot a lot with this camera? It's hardly an unrealistic option and one that many potential customers might see as tipping the balance towards them being Sony users. But they don't seem inclined to do that.
Sony go on and on about their technical achievements, which ARE impressive, but expect those of us who intend to 'push' the camera to walk around with a pocketful of batteries, or use it connected to the mains in a studio. Now Canon and Nikon don't so this. Yes DSLR's without live view screens don't consume anywhere near the power of DSLR's, but even so it was Sony's decision to dump the SLR mirror, so their often stated ambition to eat into Canon and Nikons dominance of the pro market has been 'self sabotaged' to a large extent. As photographers we really shouldn't have to be looking around for inconvenient power pack alternatives or contemplate buying expensive adapters to use some other companies lenses on our Sony cameras. And while my Canons do work very well and pretty quickly, it seems crazy that Sony can't come up with an equivalent useful set of lenses instead of the headline grabbing, 'fauxtographer' pleasing optics that they do release.
But in the end, I have to make decisions about what exists rather than what isn't there and I can probably manage. Certainly the above 4K video footage has impressed me very much and is exactly what I want. But over time I know that using this camera WILL be harder than it should be. I do believe that I will (probably) be able to come to an 'accommodation' with it, but I can't help thinking what it should be rather than the compromised beast that it actually is. I used to believe that Sony were 'the listening company', but it seems they have gone a bit deaf in recent years!!