On Wed, 10 Jul 2002 21:59:51 +0100, T.P. wrote:
>shadcat11@aol.com (ShadCat11) wrote:

>>While generally true a 50 mm f1.4 can be outperformed by its f1.8 counterpart,
>>in my experience that is not always the case. I used Pentax for a number of
>>years and at different times had f1.4 and 1.8 Super Takumars. I don't know
>>what a carefully controlled test would reveal, but I preferred the overall
>>imaging qualities of the f1.4. They seemed more "vibrant", probably a contrast
>>matter.

With Nikkors, the f1.8/2 versions were more uniform in
performance to the corners at wide stops than the f1.4,
but the late f1.4s had higher contrast at f2 and f2.8
over most of the frame than the slower lenses, so looked
"better" to those who do not care as much about corner
performance (some people appear to ignore whatever
happens in the frame corners, but I do not...).

>You're right. There is no established, verifiable "rule" that says a
>lens with a smaller maximum aperture will always be sharper than one
>with a larger maximum aperture.
>
>My experience with the Pentax range also backs up what you say; the
>K-mount SMC-PENTAX 50mm f/1.4A is optically superior to the f/1.7 and
>f/2 versions; the 135mm f/2.5 SMC-Takumar (M42) is optically superior
>to the f/3.5 version.

Often the "bargain" less expensive lens does perform worse
than the similar expensive lens in the line for marketing
reasons. In the Nikon line in the past, the "cheap" versions
generally performed as well as the expensive, but in the
last few years, this has been less true, and Nikon has been
offering relatively poorer lenses at the bottom of its line
as others have done all along. Too bad...

>In the Nikon range the 35mm f/1.4 AIS is optically superior to the f/2
>and f/2.8 versions. So it is not always a case of "smaller is better"!

Actually, I find both the excellent late MF and the good
AF versions of the Nikkor 35mm f2 both outperform the
35mm f1.4 at wide stops, though the 35mm f1.4 Nikkor is
a very good speed lens, quite useable at f1.4 at middle
focus distances... For more, see:
www.David-Ruether-Photography.com/slemn.html