I bought 3 of them on Ebay from China. B60-62, 72 and 77mm. You can buy single ones too. I had vignetting with B60-67mm adapter on Distagon CF50. Not expensive at all.
thx, if i have to fight against vignetting i can also order a heliopan 77mm filter; picture qualitiy is more important for me.
if not an adapter will be the best solution to combine my 77mm digital filters with the hasselblad system.
Even with 67mm filter and B60 adapter you should be fine with 80mm lens. You are totally vignetting safe with 77mm filter. For some reason BW contrast filters in B60 size are not very common?
Yes, there is something about quality of filters too! Last year I was lucky to find new old stock, thin Heliopan 77mm yellow for $20 in Columbus, Ohio.