I intend to get ND square filter. However, I'm not quite understand what is the function of these two and how does it uses? Did look through some examples of the photos in googles taken with those filters but seems identical to me...
Would they be the same price?
Wish to know also the price range for a basic Cokin kit (holder + ring + 1 filter).. (again the price guide forum seems pretty outdated, 2009)