I'm thinking about upgrading from the Olympus 12-50 to the 12-40 f/2.8, if I can find a good deal on a used or refurbished one. I often use a circular polarizer or neutral density filter, as well as a lens hood. I already have some 67 mm filters, and it would be much less expensive to get a 62-67 mm step-up ring so I could use them on the 12-40 without having to buy new filters. However, I suspect that this may cause some vignetting or be incompatible with the lens hood. Can someone verify? Thank you!