Manual focus only. This lens is perfect for me. Some vignetting is noticeable, but easily corrected in post-processing. I use filters but with a 46mm to 72mm adapter ring to reduce vignetting with ND filters sharpening at 5.6-11. But underneath it's still very sharp. All in all a great lens for your M4/3 collection, very small compared to others, I was between this and the Olympus 7-14 and pana 7-14. By price? Definitely recommend this if you're willing to give up the autofocus feature. I've attached some sample images. I'm giving it 4 stars because of vignetting issues.
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