Originally posted by ElJamoquio There's plenty of extra sharpness over the APS-C lens too.
There's "plenty" of difference? What does that mean? If you printed at 300 dpi, how much larger a print could you make with Nikon's 24-85 FF kit zoom shot on the D610 compared to a print made with the DA* 16-50 on a K-3? Two inches larger? Four? Seven? I see large prints from FF cameras all the time. These are prints made from images shot, not with Nikon consumer grade glass, but with Canon L glass and Nikon nano-coated glass. The difference between these FF prints and the prints I can make from my K-5 and lenses like the FA 20-35 and the DA 17-70 are surprisingly minor. At medium print sizes (like 12" by 18") you can't tell the difference (in terms of resolution) at all, and even at larger print sizes, the difference is smaller than the numerical theorists might lead you to expect.
The little extra resolution you get from FF is nice, but what really makes for great prints, particularly landscapes, is microcontrast and color rendition. I don't find FF landscape shooters, whether I meet them locally are out in the field at various iconic locations in the western U.S., shooting with consumer grade glass on their FF cameras. They're shooting with Canon L glass or nano-coated Nikkors, usually zooms.
Pentax, with its limiteds and DA* glass, allows APS-C shooters to make images that exhibit comparable microcontrast and color rendition to high end Nikon and Canon glass. You give up a little resolution, but otherwise you're able to produce images which, optically speaking, have comparable impact.
The notion that somehow the Nikkor 24-85 is a "better" lens than the DA* 16-50 strikes me as an example of mis-aligned priorities. I've seen stunning images taken the DA* 16-50 -- images with plenty of microcontrast, bite, and rich, vibrant outstanding color. I've seen no such images from the Nikkor 24-85. It's merely a very nice consumer grade lens, but hardly in the same league as high-end Canon, Nikon, Pentax, or Olympus glass. The fact that one can squeeze a bit more resolution out of that lens than one can from hi-end Pentax glass shot on APS-C cameras or high-end Olympus glass shot on m43 leaves me cold. Nowadays almost any lens/camera combination can provide more than enough resolution for the needs of most photographers. So the fact that one combination provides a little more rez is largely insignificant.