Originally posted by blackcloudbrew Even though I own a DA*50-135 and find it to be a wonderful lens, every time I've shot with one of the several old 135 primes I've owned, on any of my APS-c cameras I find that length hard to work with and just not that useful. Honestly that's why the DA*50-135 is there. It gives you a the 135 length when you need it and a lot of others at the same time. I think one could also pose the same question about why no DA 85 f1.4 and have the same answer, it just isn't that useful with a cropped sensor.
I always assumed the 50-135 was there for another reason - Reducing the need for a FF in the immediate future. APS-C with that lens is more or less a 70-200(Y'know, the ones a lot of people use on FF cameras for outdoor events and such).
Edit: Oh - And also to make Canikon users see that Pentax still makes new lenses.(Had someone ask me how long ago they stopped producing K-mount lenses once...proceeded to pull out my Helios and tell him 1966)