I have an old Cokin 67mm sq filter holder. I need to get adapter rings for it but am confused by the Cokin terminology which appears to have changed since when I last used these ( pre digital)
I'm trying to establish which type of adapter rings Ineed
The one adapter ring I have is for 49mm . The overall diameter is 60mm which is dictated by the holder I have.
Can anyone advise what series this relates to ?