Image courtesy: Photozone.
The Kowa Prominar 12mm f/1.8 MFT lens got tested at Photozone:
The Kowa Prominar MFT 12mm f/1.8 is the weakest offering in the Kowa lineup. The pure MTFs are actually quite decent. The center is always sharp at the mainstream settings and the outer image region is relatively decent at f/1.8, good at f/2.8 and very good between f/4 and f/8. However, field curvature is a major issue at large apertures so in the real life the results are less convincing here – at least in our sample which wasn’t really well centered. Typical for the three initial Prominar lenses, both the distortion as well as the lateral CAs are low which is good because image auto-correction isn’t possible. The amount of vignetting is generally on the high side though.
The Kowa Micro Four Thirds lenses on eBay:
8,5mm f/2.8 in on eBay (Click here).
12mm f/1.8 in Black (Click here), Green (Click here) and Silver (Click here).
25mm f/1.8 in Black (Click here), Green (Click here) and Silver (Click here).