Portra 160 vs 400 on the 17
I'll be camping in Denali next weekend and am wondering whether I should load my Pentax 17 with Portra 160 or Portra 400. I have used 160 with the 17 before and appreciate the sharper images it gives me, but conditions look a little variable and I wonder if I should take 400 to be safe for different light conditions—I just worry about sacrificing "sharpness," (as minute as that can be on this camera) since I don't know when I'll come back to this National Park again.
I'd love to know what more experienced 17 shooters have to say about the difference between the two stocks on this camera.
Some clarifications: I have shot Portra 400 before I have not used it on half-frame yet and I am bringing my Sony with me, so this won't be my only camera.