FYI the sensor cover glass can be removed to minimize smearing. This does take out the sensor cleaning function so I am hesitant to do it. But any company that does IR conversions should be able to do it.
This is really the crux issue for many of us. The A7 series is breeding all sorts of various versions which specialize in particular tricks, like the A7s. Now we have IBIS, which might be very nice with the long glass, really "as is", though the body is now bigger and heavier.
At this point one has to ask: why no love for the legacy and M crowd, who are largely responsible for the overall buzz surrounding the E-mount, since inception in the Nex series? When asked about the lens ecosystem, sony reps often cry: "oh, use what you like", and this would be wonderful had the design not been hamstrung by the thick sensor covering.
It appears this has not been addressed by the A7m2. The result is that while many lenses can be bolted on the A7 series, few or none perform optimally 35 and wider. Even the native 35 has some issues.The FE2470 has been a disappointment. The 1635 is apparently pretty good, but only the 55 can propel the system into the top tier today. But even that lens is marred by lack of infinity stop and really poor MF ergonomics: the focus ring is not very nice.
I've learned these things the hard way, and my A7 is simply a backup and macro/135+ rig. In both of those situations IBIS would be nice. I'm also curious how the 28/2 FE will be, and the wait has been too long for that one. Some counter that the A mount lenses make for a large ecosystem. Too "large" for me.
Add to these issues the Sony "RAWS", which, in LR, are terribly Lossy, a shadow of a the M9 dngs.
The A7 has been a huge step forward for legacy glass lovers, but simply not optimized, sad to say. Sony's biggest favor to my own photography has been to force my hand and get a M9, which I did last Jan, and 9 months later I'm completely smitten with both results and shooting experience, despite that rig's own list of quirks and less than optimal aspects.
Nevertheless we are seeing spectacular images produced with all the A7 series everyday by a plethora of great shooters. So TYG for Sony
🙂