Originally posted by Mock Yes, and I'm hoping someone will try out the DA 1.4X specifically, so the entire thing can remain weather-sealed.
I've tried this combination very quickly (and also without hood, which makes a difference for some lenses).
I hesitate to give a final judgement, but based on a quick check, there is some minor vignetting and very weak corners wide open.
Stopped right down (say to f11), the problems are limited to the very corners of the image, I would personally say it is usable depending on the application (probably fine for portraits, for example) and more broadly if a small amount of cropping is applied.
One thing I would say is that rather funky bokeh (circular swirl) is evident in some cases wide open on FF. Maybe desirable for the helios fans among us!
I would really like to make a more considered comparison of this performance with the DA 60-250 f4, which appears pretty good here on FF (for my limited purposes anyway).
John