The adaptor ring will let you mount anything that has 52mm threads, hoods, filters, whatever.
Actually, however, the 52 mm adaptor is slightly small, so you could get some vignetting if you stack filters. You might consider a bay 50 to 55 adaptor or perhaps even larger unless you already have an investment in 52mm stuff. Bay 50 to thread adaptors in various sizes are pretty common. The 52 will work though, and there are even bay 50 to 49mm adaptors.
As for the shutter, I find it easiest to just hold down the release for a second or so routinely. it doesn't particularly matter how long you hold the rear curtains open, and you are assured that you'll never cut off a longish exposure by releasing too soon. YMMV though.
I see no reason not to simply use bay 50 filters, I have standardized on bay 60 filters and it seams like just using the hasselblad filters would be easer the having to use an adaptor.
True. But B50 filters are scarce used (especially in good condition) and both scarce and expensive new. I have a couple for my C lenses, but rely on a B50 to 55mm adapter.
Originally Posted by cjbecker
I do like the H'blad hoods. They mount "outside" and independent of the filter mount, so usable with my adapter or B50 filters. And presumably carefully matched to the angle of view of the lenses.