This is a very rare lens. Or maybe not so rare because you can still find them at ebay.
The lens diameter is so huge that it can hide the whole camera body behind it.
Got this lens from a late dealer friend. I tried this lens before, it is quite soft and does not spark my interest in it.
Yesterday was a bit free, so I took the lens and mounted it on my Nikon D810 to play around. Captured some photos around ShaShinKi shops.
At F/2.8, the image is quite soft. I stop it down to F/4, it is getting much better sharpness. Then stop down to F/5.6, it is amazingly sharp!
There are still some purple fringing at the circular edge of the photo, but does not matter to me.
The full view of ShaShinKi shop from outside.
Full view of ShaShinKi retail shop in 180 degree.
Now, the lens + D810 body.