OK, first impressions from use - I wonder if my lens got 'kicked around', because I've had an intermittent electrical fault. Went for a wander, and this was the first shot :
Viltrox FE AF 85 f1.8 PFU RBMH by
Toni Ertl, on Flickr
Yup, completely failed to get focus. Sometimes it was OK, sometimes I got focus peaking highlights over stuff in the viewfinder, and eventually I got a message about lens lot recognised or not mounted properly - I unlocked & re-seated it and the lens then behaved normally. Fairly sure this copy is going back.
All images as near to SOOC as possible, default Lightroom sharpening only, low sharpening for screen on export, no other adjustments apart from the one grass image cropped to 100%.
However, next attempt, f1.8 because it had to be done:
Viltrox FE AF 85 f1.8 PFU RBMH-2 by
Toni Ertl, on Flickr
Optically it's not bad at all, and the rendering is really nice as it transitions from in to out of focus. f8 and it's sharp across 90% of the frame with softness in the far corners, bit it gives a pleasing 3D look to separate objects in the frame.
Viltrox FE AF 85 f1.8 PFU RBMH-3 by
Toni Ertl, on Flickr
f8 again.
Viltrox FE AF 85 f1.8 PFU RBMH-4 by
Toni Ertl, on Flickr
100% crop (you'll need to go to Flickr to see it).
Viltrox FE AF 85 f1.8 PFU RBMH-5 by
Toni Ertl, on Flickr
Bokeh demo against a dark background.
Viltrox FE AF 85 f1.8 PFU RBMH-6 by
Toni Ertl, on Flickr
Bokeh demo against a light background.
Viltrox FE AF 85 f1.8 PFU RBMH-7 by
Toni Ertl, on Flickr
There's a bit of purple and green fringing from CA in high contrast situations, but it's not bad and much less than my Sony A mount 50 f1.4 (both a bokeh and CA monster).
I need to see what version of firmware it's running, perhaps upgrade, check out reliability. Optically it's good in terms of sharpness, great for rendering. AF-wise it's not so good, mostly I suspect because the electronics aren't working right, rather than something inherent in the lens. Right now the Sammy 85 f1.5 is looking increasingly attractive.... if only it weren't so large.