Originally posted by ffking I'm pretty sure the one on the road map will be based on the Tokina - hence the speed of delivery, and they'll never put a star on anything that isn't their own optical design (as well as the other criteria), but with Pentax coatings it should be more than adequate - you seldon get perfectly clear air all the way to the mountains, so the resolution etc needed for portraits is wasted on landscape most of the time.
I'd really have to see how it performs before jumping. I am reasonably ok with weight, but do miss the 60-250 I used to have (the vignetting bugged me just a little too much on FF).
I think corner/edge weaknesses are the thing I usually struggle with on landscape. This can be quite pronounced when there are foreground elements in the composition, e.g. rocks, plants etc to 'set the scene' and establish the scale. That said, many of the problems here relate to field curvature and are far more pronounced on wide angle, so I would not expect a modern 70-200 F4 to be a big headache in this regard. Let's hope it is reasonably well engineered and properly weather sealed!
And roll on the (presumably super-heavy) HD D-FA* 85 1.4 as well!
John