Arguably one of the worst lenses Pentax ever sold is the SMC-A 35-80/4-5.6, which is lousier than any Tak I know of. And arguably almost every newer zoom is optically better than an M42 zoom -- with notable exceptions such as Vivitar Series 1 and some other premium lines. But to toss-out all M42 primes, you discard many masterpieces by Zeiss, Asahi Pentax, Meyer, Tomioka, et al.
My fastest lenses, other than the superb K50/1.2, are FA and ST 50/1.4, planar Yashica ML 50/1.4, and Tomioka 55/1.4. Only the FA50 is SMC, but I use hoods on all these. And all give different (and excellent) results. The ST and FA 50's are similar but not identical, and of course they feel different to use. My next fastest are a batch of old lenses around 50-55/1.7-1.8, by Asahi Pentax, Chinon, Mamiya, Meyer, Olympus, Petri, Ricoh, Yashica, all being different to use and value. These, and slower Fifty's from Asahi Pentax, Cosina, KMZ (Russian), Meyer, Porst, Ricoh, Zeiss, all produce excellent (and different) sharp results when stopped-down.
These will show different dimensionality, color renderings, bokeh,
character. From f/4 and up, I prefer the bokeh of the CZJ Tessar 50/2.8 (12 iris blades) and the sharpness of the Macro-Takumar 50/4 (1:1) to the FA50/1.4. I love the dimensionality of the Yashica ML 50/1.4, the Tomioka 55/1.4, the Petri CC and Super-Takumar 55/1.8's, etc. Are any of these
better or worse than newer AF Fifty's? I can't say that; just that they're
different.
I have a mantra. (I have
many mantras -- this is just one). Newer AF zooms are good for taking pictures; older MF primes are good for
making pictures. Many newer lenses will fairly accurately record what's around you. Many older lenses help you capture what you
want to see. What we want to see; what we think we see; what the camera sees; and what is really there (if anything); these are not the same. Each lens is like an artist's brush, a different instrument for producing different images. And each lens is a different window on the world. That's why I have hundreds of lenses, to look through those various windows, to use those varied instruments. It's aesthetic, not technical.
Last edited by RioRico; 05-08-2011 at 07:22 AM.