Hmmm. Not as good as the RX-1 lens but it doesn't have the midfield weakness of that lens.
Possibly a little better at the edges than the Sigma 35mm ART on the D800, in terms of resolution, but even with shading corrections turned on in camera, there is still quite some colour shading going on, especially at F2.8
The lens is nowhere near as good at the edges as the 35 Lux FLE - you might argue that at a fraction of the price this is not surprising but then as an F2.8 lens, designed specifically for this camera, there might have been less of a difference.
Some inconsistent behaviours that might imply a mild focus shift and a mild field curvature working together to confuse me. Edges sharper at F2.8 and F4 than at F5.6.
Diffraction is from F5.6 onwards but appears to stay pretty constant from F5.6 thru F11.
F4 is the 'best' overall aperture from my limited tests so far.
Here's an F2.8 file shot using Shading Compensation, followed by the same file corrected in LR with flat field plugin from a calibration file shot at the same time:
In other words, the shading compensation is, as with the RX-1, partial only.
This is a very key lens for the A7R - as the first one available in FE mount, and at a relatively rich price, it is the single lens that most lays down Sony's intentions for the range and therefore for the entire A7 system. It is probably going to disappoint a fair number of people and might therefore raise questions over the entire system. But it is worth noting that it is tiny, light, has a great hood (more a shade really) and as I say above, seems to have better edges than the lens that many people think is best in this focal length for the Nikon D800E.
Oh, and 35mm? My a$$. You get maybe up to 5mm worse than that for your money - it seems closer to a 40mm...