In article <1995Dec4.162833.11990@sol.UVic.CA>, tbuckley@sol.uvic.ca says...
>Is the Nikon 50 mm 1.4 AF worth $200 more than the 1.8 (discouinting >the fact that the 1.4 is available as aD lens). (...)

No. The AF, E, AIS (plastic barrel), and AIS (compact metal barrel -
a rare version I am happy to own) are the same excellent optical design,
except that some versions are multicoated, some not (the difference
in performance with different coatings is subtle at best). This lens does vary a bit from sample to sample, but of the MANY I have checked,
none has been poor (they vary from good to excellent at wider apertures). The f1.4 is sharp over most of the frame wide open, but is
low in contrast. By f2, it is excellent over most of the frame (a bit
better, maybe, than the f1.8, except at the edges/corners), but the edges/corners, while not soft, are clearly not up to the center performance (the f1.8 is more even). After about f4, it would be hard
to tell the difference in the two lenses - both are excellent. Other
ways the two lenses differ: the f1.4 has slight barrel distortion -
the f1.8 has no distortion; the f1.8 performs better near minimum focus, and much better on tubes than the f1.4; the f1.8 is lighter, and in
some versions, much smaller than the f1.4.
Hope this helps.