Originally posted by BarryE ... the SMC Pentax-FA 50mm F1.4 is (very) poor wide open. But here's the thing, for me, at f5.6/f8 for portraits its fine...
A lot of this stuff is just subjective.
That's a perfect example. I'd agree, the FA50/1.4
is poor wide open in terms of resolution... and yet, there are folks (I'm one) who like the way it renders at maximum aperture for certain use-cases; so, the value of the lens at widest / wider aperture is relative to the individual's expectations and requirements...
This leads me to wonder what the OP's application / use-case is that would benefit from precise resolution data. It's certainly become fashionable for lens review sources to publish and draw conclusions from MTF data, but aside from a few very specific use-cases, I'm not sure how valuable that data really is. Personally, I find it more useful to know at what apertures a lens is soft away from the centre and in the corners... what aberrations it "suffers" from (and which may actually contribute positively to its rendering, given my own personal preferences)... vignetting... flare performance in strong light... etc.
You're right, Barry... a lot of this is subjective - and knowing not just what you
think you want from a lens, but
why (i.e. "
does it really matter?")...