Hi all ye owners/users of the CV Nokton 17.5mm! I'm about to press the 'buy now' button and I had one last question... I've read in several reviews about field curvature issues with the 17.5mm, including this one from Pekka Potka (who I have a lot of time for) - "Another note must be made on focus plane. It is not straight but curved so that it curves closer to the camera towards image edges." Now, my question. I plan to use this lens for quite a lot of landscape work (amongst other things) - have any users of the lens found field curvature to be noticeable in real-world use? I mean when photographing three dimensional landscapes, rather than brickwalls or test-charts If you have experienced it, how do you deal with it? Can you just focus for the corners and let depth of field take care of the centre? Any experience would be great (experience only please - I don't care what such and such said on the DPR forums...) Cheers in advance!