Originally posted by Adam I'd say either the DFA * 70-200mm or the DA* 60-250mm, both with the 1.4x teleconverter. I'd lean toward the former as it's just stellar in terms of sharpness, especially in crop.
I'm going to concur with Adam. I posted my first photo with the lens in the K-1 shots thread.
I've played with the [FA Limited] 31mm, 43mm, 77mm, [DA Limited] 15mm, 35mm, 40mm, [DA*] 16-50, 50-135, [D FA] 28-105, 100 and the 8-element Super Takumar 50mm f1.4. They've all been renowned for good reasons, but I've never been so compelled as with the 70-200 to call something
optical perfection. You're paying for it -oh, you're paying in weight, cash and bulk- but it is remarkable. Post-processing was totally superfluous: distortion is compensated for, flaring is well-controlled, even without the hood, the image is rendered evenly in a very nice and smooth way on the K-1 sensor (a sensor I really like).
I've never had a lens' optics and construction come together so well to produce what my mind wanted to create (even if the photo isn't that stellar in retrospect
). In any case, highly recommended, on any format.