The Nikon G Lens to Fujifilm X-Mount Camera Speed Booster from Metabones allows a full frame Nikon G lens to be mounted to a Fujifilm X-mount APS-C format camera and in doing so, increases the angle of view and increases the maximum aperture one f/stop.
When a lens intended for full frame sensors or 35mm film is mounted to a camera with an APS-C sized sensor, it transmits a larger area of light than the smaller sensor was built to accept and therefore the angle of view of the lens decreases and the equivalent focal length increases. The Speed Booster condenses light from the lens and projects it onto the APS-C sensor allowing the sensor to utilize all of the lens′ light and effectively produce a full-frame angle of view with an APS-C sensor. A corresponding increase in the maximum aperture of one f/stop makes the lens more effective in low-light situations and able to create a shallow depth of field.
Metabones Speed Boosters are quality made, using precision-machined brass with chromium plating on both the camera-body and the lens sides of the booster in order to ensure smooth mounting, quality aesthetic, and durability. This adapter has a detachable tripod foot that is compatible with Arca Swiss, Markins, and Photo Clam ball heads.
Although the lens will fit physically, automatic diaphragm (AE metering), or other auto functions are not retained using this speed booster. The Nikkor 2.1cm f/4 and 20mm f/2.8 AI-S lenses are not compatible with the speed booster.
The aperture control ring on the Nikon G Speed Booster is a clickless aperture ring, optimized for shooting video, however parts and instructions are included to modify the ring to a clicked version if the user so desires.