Canon EF - E-mount T Speed Booster ULTRA 0.71x

by Metabones

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 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.


  • 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 pending).
  • Felt material flocked inside the opening to reduce internal reflection.
  • The tripod foot is detachable and compatible with Arca Swiss, Markins, Photo Clam ball heads.


  • Fast contrast-detect AF on all E-mount cameras.
  • Phase-detect autofocus support on A7RII, A7II and A6300.
  • Smooth iris support with the latest Canon (2009+), Tamron (SP series 2013+) and Sigma (2016+) lenses
  • Supports 5-axis in-body image stabilization of A7II, A7RII and A7SII. (Distance information from lens required; 3-axis IBIS if lens does not transmit distance information.)
  • Powered by camera body. No external power source required.
  • Aperture control from camera body.
  • Custom function button assignable to more than 50 functions on A7 series and A6300.
  • High performance 32-bit processor and efficient switched-mode power supply.
  • Supports image stabilization (IS) lenses.
  • Supports electronic manual focusing (e.g. EF 85/1.2L II and discontinued EF 50/1.0L)
  • EXIF support (focal length, aperture, zoom range)
  • Distance and zoom display on VG and FS series camcorders, A7 series and A6300 (lens with distance information support required).
  • Auto magnify (lens with distance information support required)
  • Auto "APS-C Size Capture" on full-frame cameras.
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