The industry's best aperture ring covers an 8-stop range with markings clearly indicating actual number of f-stops. Compatible with both Nikkor G lenses & F lenses (including non-AI & AI lens mounts).
An advanced 5-element/4-group optical design incorporates ultra-high index tantalum-based optical glass, and increases maximum aperture by 1 stop while also making the lens 0.71x wider. The tripod foot is detachable and compatible with Arca Swiss style ballheads.
Before mounting your lens to the adaptor, please make sure that the f-stop of aperture ring on the adaptor is turned to "7" (i.e. mounting your lens to the adaptor while only the aperture ring in the adaptor is full closed.). This mount is manual aperture control. It does NOT support electronic aperture control.