The Speed Booster Ultra 0.71x Adapter for Sony A-Mount Lens to Fujifilm X-Mount Camera from Metabones allows a full-frame Sony A-mount lens to be mounted onto a Fujifilm X-mount camera. While doing so, the adapter's optics help to maximize the connected lens's apparent angle of view while providing a 1-stop increase for the camera over the lens's aperture range.
If a lens intended for 35mm film or similarly sized full-frame camera sensors is connected to a camera with a Fuji X-mount APS-C-sized sensor, it would project an image larger than the Fuji X-mount APS-C sensor was built to accept. Able to capture only the center portion of the projected image, the effective angle of view of the lens would be narrowed, creating an in-camera "crop factor." The Speed Booster Ultra 0.71x Adapter for Sony A-Mount Lens to Fujifilm X-Mount Camera condenses the light from a lens designed for 35mm film or "full frame" camera sensors and projects it onto a Fuji X-mount APS-C sensor. This allows a Fuji X-mount APS-C sensor to utilize more of the light gathered by a connected lens, which effectively reduces the crop factor while making available to the sensor an additional 1 stop of light for each of the lens's f/stop settings.
This adapter is constructed from aluminum alloy for durability while minimizing weight and its mounting rings are made with brass to further prevent wear-and-tear. Inside are five lens elements in four groups that are designed to provide optical clarity as well as color fidelity, and a detachable tripod foot is included that features 3/8" threads as well as compatibility with Arca-Swiss tripod heads.
The Speed Booster Ultra 0.71x Adapter for Sony A-Mount Lens to Fujifilm X-Mount Camera does not support electronic communication between an attached camera and lens. To help determine the amount of light that enters a Fujifilm X-mount camera when using this adapter and a Sony A-mount lens, an aperture dial is built into the Speed Booster Ultra 0.71x Adapter for Sony A-Mount Lens to Fujifilm X-Mount Camera.