I've come to a conclusion: some of the shooting I'm trying to do at the moment needs a graduated neutral density filter. After a bit of asking around and net searches, I'm thinking that the Cokin system is a good way to go: ability to rotate the line between the two sections, as well as shift it across the lens, is a major plus (compared with a "traditional" filter, where you'd have no choice about where on the lens the line crosses, although you can rotate it.) All well and good. It's not all that expensive, either - $AU40 per filter, plus $AU50 for the holder, from my local B&M camera shop (at least for the graduated filters; I haven't priced any others - mainly because I don't yet have the need or money for them). This leaves me pondering the question of circular polarisers. I can get a 77mm high-quality (super pro 1, I think from memory) Hoya for $AU175 (plus step-up rings so I can use it on my other lenses, with their 67mm and 52mm filter threads, for around another $AU50 or less). Alternatively, I can get a circular polariser that goes into the Cokin system (price unknown; I don't have the money to buy filters willy nilly, so it'll have to wait a month or two either way). Anybody have any thoughts on the pros and cons of the two different approaches for the circular polariser? On the Cokin system in general? Equivalent systems from other manufacturers? I really like the idea of the flexibility that Cokin seems to offer, but more information before making the purchase would be nice. Many thanks.