Originally posted by hwblanks I think the *50-135 could be useful for street work if you're shooting people from a distance either further down the same side of the street or across the street. For buildings, you're better off going with one of the wider choices.
HTH,
Heather
What Heather said.
Also, the Tamron/Pentax 18-250 is an excellent choice if you're going to want both wide-angle architecture and up-close people shots.
IQ-wise, the DA* 50-135 is the absolute best possible choice for mostly-people shooting.
If budget is an issue, the SMC-M 135mm f/3.5 or Super Takumar 135 f/3.5 are wonderful, and can pretty much get you IQ as good as the DA* 50-135 at 135mm.
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