H&Y Revoring variable step-up rings allow filters to fit multiple lens thread sizes
Filter manufacturer H&Y has launched a series of new step-up adapter rings that have variable thread sizes to allow users to fit a single screw-in filter to multiple different sized lenses. Using a sprung iris the thread size of the Revoring can be altered to fit a range of lens sizes via a rotating ring on the adapter. The idea is a single screw-in filter can be switched between different lenses very quickly without the need for changing adapter rings.
There are four sizes of Revoring to cover lens threads of 37-49mm, 46-62mm, 67-82mm and 82-95mm. The 37-49mm ring, for example, takes a 52mm filter. Once attached to the Revoring that filter can be switched between lenses that use filter thread sizes of 37mm to 49mm, by twisting the revolving ring to adjust the size of the adapter’s thread.
Twisting the adjustable ring closes the iris to its smallest size, and releasing it allows the thread to expand to fit the lens in use. The adapter holds in place immediately, but can be screwed in for extra security. To take the adapter off the lens the ring is turned to again contract the iris so it comes free of the lens.
Each of the sizes comes as a stand-alone ring for users to attach their own filters, or a second version is available that has H&Y’s variable ND filter with a circular polariser already built-in. The variable ND ranges from ND 3-1000 covering light reductions of 1.5-10 stops.
I've had couple of the rings for a while and thought a video would explain them a little better.