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Incredibly interesting answers here. I have a lot of thoughts (agreement/disagreements) on a lot of these, but I'll just quickly post my two, as I have to get to work:
DA 14mm
This is well loved, even revered by many - but the DA 14 is not small, it's not a DA* or a limited, and it's not cheap - and, as far as I've seen, the 12-24 does just as good a job at 14mm, and is much, much more versatile.
I saw the $375 one appear in the marketplace, and I could have been the first bidder, but...
I love primes to death, and I almost always prefer putting them on the camera, but I just don't get this lens.
Pentax 50mm f/1.2 (K, A, any)
It just costs too much. I know this lens won scarpents 'normal lens shootout', but I think that's because he wanted it to win - it was already his favorite lens, IQ aside.
I've always asked myself: is the 1.2 --> 1.4 difference worth the extra $300? And all the images I saw said.... No.
Since I've discovered the Cosina 55 1.2, I
get the 1.2 aperture more now - but the Cosina cost me $200, and that was about all I was willing to spend to get what I consider a specialty lens. (IQ-wise, I think the Tak 55 1.8 is every bit as good as the Cosina, BTW, it just doesn't have that big eye.)
So there are my choices - flame away!!
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