The new Metabones EF to E Mount T lens adapter with Speed Booster Ultra features advanced 5-element/4-group optical design incorporating ultra-high index tanatalum-based optical glass to achieve extraordinary optical performance with improved corner sharpness, distortion and reduced vignetting.
The Speed Booster ULTRA has a magnification of 0.71x; effectively reducing 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 fullframe 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.
MB_SPEF-E-BT2 Features:
Increase maximum aperture by 1 stop.
Increase MTF.
Makes lens 0.71x wider.
Advanced 5-element/4-group optical design incorporating ultra-high index tanatalum-based optical glass by Caldwell Photographic in the USA (patent pending).
Electronic integration of aperture diaphragm, controlled by or from the camera body.
Partial autofocus support for late-model (post-2006) Canon-brand lenses.
Powered by camera body. No external power source required.
High performance 32-bit processor and efficient switched-mode power supply.
The tripod foot is detachable and compatible with Arca Swiss, Markins, Photo Clam ball heads.
Flocking material coating inside the inner hole to reduce the internal reflection.
Note: Metabones adapters are NOT licensed, approved or endorsed by Sony or Canon.