Metabones Contax Yashica CY to X-mount Speed Booster ULTRA 0.71x CINE (MB_SPCY-X

Metabones Contax Yashica CY to X-mount Speed Booster ULTRA 0.71x CINE (MB_SPCY-X-BM3)

• Increase maximum aperture by 1 stop.
• 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).
• Positive-lock CY lens mount, the robust cine-style positive locking mechanism to ensure that no play when attaching the vintage lenses ;
• Detachable Arca-Type tripod foot compatible with Arca Swiss, Markins, and Photo Clam ball heads(clamp directly or attach to quick release plate by a 1/4-20 screw).

The following lens(es) have a protruding rear element and may not be compatible with or may require modification to fit the Speed Booster:

• Distagon T* 3,5/15

This adapter is a mechanical adapter. It does NOT support electronic aperture control, AF and EXIF.

Speed Booster ULTRA

Sharper corners, less distortion, reduced vignetting 

New optical design:  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.

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.