|DA* 50-135mm f/2.8|
The * lenses are Pentax' headline, pro-caliber lenses; DA* for aps-c sensors while FA* is for 36×24 types. The 50-135mm f/2.8 arrived yesterday, but it came to the house while were were away - so I've just picked it up today. I parked across the street from the Post Office at the central Longview city park for a few tests against the 55-300mm set at 55 and 100mm and f/4. I have not compared the images yet, but images from the DA* have an oh-my factor that cannot be ignored. Images do indeed look 'primal' even if just on the K-r rear screen at moderate zoom. The DAL 55-300 is no slouch optically so side-by-side checks will be fun.
As to mass, the 50-135 is a fairly bulky lens, similar in length to the 55-300 but considerably thicker and more dense. Larger and more pieces of glass will do that. It's not so bad that it will stay behind on hikes, but it does have that 55-300 to compete with! The lack of WR on my copy of the latter does suggest that the DA* is a fine choice for outdoor travels despite the extra 350 grams.
The real DA* benefit comes from this lens taking over the duties of all primes in the 50-135mm range, which is why the M85/2, M100/2.8, A100/4 macro and M150/3.5 have left the building (or will soon). The A50/2 and M135/3.5 have no resale value (they go for $20-30 on most sites) so they will keep the K24/2.8 company in the classic-prime box. One from each generation, how nice!
I'm contemplating a future where a 1.5x teleconverter makes this a longer f/4 lens; probably not the worst idea I've had. Not yet though!!