My Cokin P series filter system is causing vignetting with the 14-35 f/2 when it is used in conjunction with a polarising filter screwed onto the lens.
Cokin make a filter holder for wide angle lenses, the BPW400A, which should solve the problem, but some reviewers say that it has not solved their vignetting problems, albeit with different camera/lens combinations.
Anyone here had experience of the BPW400A on the 14-35 f/2?
Unfortunately we don't have a shop where I can go and try it out for myself.

Guy