All ratings are based on my experience with these lenses on my fullframe Sony Alpha 7.
Minolta MD FISH-EYE Rokkor 16mm 1:2.8 (3-3.5/5)
f/2.8: The center is excellent, and most of the image sharp enough, midframe sharpness is actually lower than near corner sharpness wile the far corners are unsharp. Vignetting is surprisingly low.
f/5.6: noticeably better than f/4, most of the image is very sharp, only the far corners are unsharp
f/11: very good sharpness across the frame. Flare resistance is average and CA pronounced.
A rather heavy lens with integrated filters and lens hood. Built quality is excellent
Fisheye lenses are very hard to master, I wasn’t really succesfull at it. But this is a good lens, so good in fact that it also came in Leica R-mount and the same optical design is still used by the current Sony 2.8/16 Fisheye.
There is a younger MD version which is supposedly not as good.
I have owned the Canon FD 2.8/20 for about a year now and I am mostly happy with it’s performance. Now I got the chance to test it against the smaller and lighter Minolta MD 20mm 1:2.8. So, how do they compare?