MB SPEF-E-BT4 NEX -EF ULTRA IIEAN  4897050182222

Speed Booster ULTRA for E-Mount and X-mount cameras

Sharper corners, less distortion, reduced vignetting

New optical design: advanced 5-element/4-group optical design incorporating ultra-high index tantalum-based optical glass to achieve extraordinary optical performance with improved corner sharpness, distortion and reduced vignetting.

Like the revolutionary original Metabones Speed Booster announced in January 2013, the Speed Booster ULTRA has a magnification of 0.71x, and so it effectively reduces the crop factor of mirrorless cameras with DX-sized sensors, such as Sony E-mount and Fuji X-mount cameras, from 1.5x to 1.07x. However, the new ULTRA design makes very effective use of exotic materials at the furthest limit of glassmaking technology, and as a result is well corrected for use with virtually all full-frame SLR lenses regardless of exit pupil distance. Thus, the Speed Booster ULTRA performs extremely well with professional-grade f/2.8 zoom lenses such as the 24-70mm f/2.8 and 70-200mm f/2.8 zooms by Canon and Nikon to produce 17-50mm f/2.0 and 50-142mm f/2.0 high-speed zooms, respectively. Similarly, high-speed fixed focal length lenses such as a 50mm f/1.2 will be transformed into a 35.5mm f/0.9 lens with excellent contrast and resolution from the center all the way to the edges of the image.

Features and benefits

Metabones Exclusive

Advanced 5-element/4-group optical design incorporating ultra-high index tantalum-based optical glass by Caldwell Photographic in the USA (patent pending).
If both your lens supports optical image stabilization (OIS) and your camera supports sensor-shift, in-body image stabilization (IBIS), the choice is yours on which one to use, or have both of them work in harmony.
Smooth iris support with the latest Canon (2009+), Tamron (SP series 2013+) and Sigma (2016+) lenses.
Custom function button (called Focus Hold button) assignable to more than 50 functions, such as Aperture Preview and Eye-AF, on A9, A7 series, A6500 and A6300.