Metabones T Speed Booster ULTRA 0.71x Adapter for Canon EF to EF-M Mount Camera

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(APS-C), 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.Key FeaturesOptical• Increase maximum aperture by 1 stop. (with a maximum output aperture of f/0.9)• Increase MTF• Makes lens 0.71x wider• Advanced 5-element/4-group optical design incorporating ultra-high index tantalum-based optical glass by Caldwell Photographic in the USA (patent granted)Electronic• Autofocus. AF speed is properly adjusted to account for and leverage the shorter focal length and the brighter maximum aperture• Focal length and aperture are adjusted in EXIF• Image stabilization (IS) lens support• VIdeo Digital IS support (on supported camera bodies)• Store EXIF data (lens name, focal length and maximum/minimum aperture) for one manual lens in the adapter• LED indicator shows communication status• Powered by camera body. With most lenses, no external power source requiredMechanical• The tripod foot is detachable and compatible with Arca Swiss, Markins and Photo Clam ball heads• Flocking to reduce internal reflection• Rubber gasket protects EF-M mount connection from dust and moisture• Aluminum alloy and brass construction with chromium plating• Satin surface finish