All lenses shown here consist of seven lenses. Some of them are using the [7/5] design, many the [7/6] formula. 

The background blur of all the nine 1.4/50mm lenses tested is very similar. Slight differences can be found, however. The Super-Takumar 1.4/50mm, a legendary lens from the 1960s, certainly has the "noisiest" bokeh (apart from the fact that its radioactive glass causes a strong yellowish color cast). The only 1.2/50mm design in this test doesn't differ significantly from the f1.4 lenses.

The bokeh of all the f1.4/50mm and f1.2/50mm is nowhere as smooth as the 58mm lenses (be it f1.2 or f1.4).

Canon FD 1.4/50mm SSC, one of the earliest f1.4 lenses with the [7/6] formula. The lens, introduced together with Canons first professional F-1 SLR, immediatly had a very good reputation for its detail resolution. Its bokeh is a bit on the harsh side, not unlike the Minolta MC-X 1.4/50mm from the same time.  

Canon new FD 1.4/50mm, the successor of the above FD 1.4/50mm, feels much lighter and smaller. It has noch "breech-lock" mount any more, but an internal mechanism allowing to mount the lens similar to lenses from other manufacturers. Its bokeh seems to be slightly smoother.  

Mamiya Sekor CS 1.4/50mm, a lens introduced 1978 for the NC-1000 SLR. Mamiya always had a reputation of building excellent normal lenses, and the Sekor CS 1.4/50mm is a beautiful example of well balanced aberrations (not unlike the second version of the Nikkor 2/50mm). Even in the corners the "blur disks" are quite round, thus avoiding a "swirly bokeh".

Minolta MC 1.4/50mm - the first fast 50mm lens from Minolta (previous 1.2, f1.4 and f1.7 designs had been 58mm and 55mm, respectively). The lens is heavy, extremely well built, and focusing is perfectly smooth even after 40 years, due to "brass on aluminium" helicoids like Leica. It's bokeh, however, may be slightly harsher than the later Minolta MD-III 1.4/50mm. Not a big difference, however ...

Minolta MD 1.2/50mm - its bokeh is nearly indistinguishable from the better f1.4 lenses. This isn't a big surprise since it's fromt lens isn't much bigger than that of the Minolta Rokkor MC 1.4/50mm or the Hexanon AR 1.4/50mm. In the image center the blur may be a bit better than with f1.4 lenses, but in the corners there's certainly not much difference.

Minolta MD 1.4/50mm - the latest MD-III version shown here somtimes is said to be not as sharp as the MC 1.4/50mm. This obviously isn't true; i have tested several MC 1.4/50mm and MD 1.4/50mm, but could not verify this rumor. The bokeh of the late MD 1.4/50mm is a bit smoother (round shapes instead of mushroom-like heads), but nothing to get excited about.

Konica Hexanon 1.4/50mm: This lens is a bit unusual due to its large front element (similar in size to the Minolta 1.2/50mm!). Like most Hexanon primes, the lens is very well built, but focusing is nowhere near as silky as with the Minolta MC-X and early MD-I lenses. At about CHF/USD/EUR 30 - 50.-- the lens certainly is a bargain.

Nikon Nikkor 1.4/50mm: The second computation from 1976 shown here certainly is a classic design. Mechanically clearly inferior to the corresponding Minolta MC 1.4/50mm, its bokeh is very similar to the Canon new FD and Minolta MC/MD 1.4/50mm lenses.

Pentax Super Takumar 1.4/50mm: Another classic lens, though ten years older than the above Nikkor. Partly made from radioactive Thorium glass, the lens is quite "hot" (about 20 microsievert/h on the surface). When it hit the market, the Super Takumar 1.4/50mm was regarded as one of the best (if not the best) fast standard lens. It has, however, the noisiest bokeh of all 50mm 1:1.4 lenses tested here.

Zeiss Planar CY 1.4/50mm: Again a classic lens. Computed by Glatzel at Zeiss Oberkochen in 1972/73, it later became the standard lens for the Contax RTL (1974). The lens always enjoyed an excellent reputation because of its detail resolution, its low distortion (about 1.5%) and its freedom from lateral CAs. Its bokeh is similar to the rest of the bunch, maybe a bit to the smoother side - but the differences between the 50mm 1:1.4 lenses are merely academical (apart from the Super Takumar, maybe).