So...my fancy 82mm B+W ND filter is really stuck to my "bargain" step-up ring. Have tried my usual tricks...including using two light cords in opposite directions, and dunking the step up half into boiling water. Problem is, the seizing together took place as I was photographing surf - and my guess is that there has been some salt-related welding between the brass and aluminum components (why I tried the boiling water).
Anything else I might try before I fire up my dremel? (to use cutoff wheel to remove step up ring). Thanks!
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