Canon EF Lens to Fuji X mount T CINE Speed Booster® ULTRA 0.71x

Key Features


  • Increase maximum aperture by 1 stop. (with a maximum output aperture of f/0.9).
  • Increase MTF (details).
  • 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).


  • Canon EF mount lens to Fujifilm X-mount camera.
  • Autofocus. Phase-detection autofocus (PDAF) is supported no matter which AF lens is used. Adapters support PDAF by translating pertinent metadata about the optics between the lens interfaces. In this way, broad support of the widest range of lenses is made possible.
  • Lens iris/aperture is set by the controls on the camera body.
  • Fujifilm XF Teleconverters support.
  • Optical image stabilization (IS) lens support.
  • Smooth iris support with the latest Canon (2009+), Tamron (SP series 2013+) and Sigma (2016+) lens models.
  • Focal length and aperture are adjusted in EXIF (see note 3).
  • Store EXIF data (lens name, focal length and maximum/minimum aperture) for one manual lens in the adapter.
  • Parallax correction on the X-Pro series rangefinders is also supported.
  • LED indicator shows communication status. 
  • Powered by camera body. With most lenses, no external power source required.


  • Patented positive-lock EF lens mount.
  • Flocking to reduce internal reflection.
  • Rubber gasket protects the X-mount connection from dust and moisture.
  • Aluminum alloy and brass construction with chromium plating.
  • Satin surface finish.
  • Detachable tripod foot compatible with Arca Swiss Style ball head, such as Markins and Photo Clam or attach to quick release plate by a 1/4"-20 screw. 



  • Each lens needs to go through a calibration procedure<click to view> when first used. EF-X Mount Speed Booster ULTRA or EF-X Mount Smart Adapter will gather metadata by turning focus to infinity and minimum when the power is turned ON for the first time. If the lens has a focus limiter switch, set it to FULL prior to turning on the camera. Set camera to AF-S and use the autofocus a few times, although during the initial calibration stage the AF performance may be subpar and you may experience difficulty locking onto subjects. For a zoom lens, it is also necessary to zoom to both the wide end and the telephoto end of the zoom range. Turn off the camera to complete the calibration procedure. If calibration is successful the Speed Booster ULTRA or Smart Adapter will no longer turn focus to minimum the next time the camera starts up. If this calibration procedure is not completed properly, there may be problems such as excessive hunting, difficulty locking onto targets, inaccurate AF, incorrect parallax correction on X-Pro series and incorrect distance scale display on the camera (if enabled).
  • Continuous autofocus (AF-C) and video autofocus may not work on some cameras such as X-T100. Increasing FOCUS SENSITIVITY and decreasing AF SPEED is required under the AF-C CUSTOM SETTING (MOVIE) menu.
  • For video, aperture priority or manual exposure is recommended to avoid exposure flickering. Fujifilm cameras require fine aperture control but EF lenses are not capable of controlling the aperture with sufficient granularity.
  • AF+MF and lens aberration correction are not supported. 
  • Some early film-era lenses have a large amount of backlash and may not be able to achieve the AF accuracy required for digital cameras. Old lenses with faulty sensors due to wear and tear may lead to AF problems on a mirrorless camera even though the lens may appear to function normally on a DSLR.
  • Distance displayed by camera is approximate but may not match the lens' distance scale. Older optics which do not report distance information will display an incorrect distance on the camera.
  • Parallax correction on X-Pro series is approximate and may not be accurate. Older optics which do not report distance information do not support parallax correction at all. All but the smallest EF lenses block a significant portion of the optical viewfinder.
  • AF Range Limiter is supported only on newest Fujifilm cameras and require distance information support from the lens. If the option is greyed out try setting it in movie mode.
  • Lens aberration correction is not supported.
  • Speed Booster ULTRA not only boosts the maximum aperture of the lens, but minimum, too. It is no longer possible to go down to f/22 or whatever else the minimum aperture of the lens is.
  • The adapter has no aperture ring. On a camera with no mode dial, configure the "APERTURE SETTING" menu option to "AUTO+MANUAL" and use the camera's front or rear dial to change aperture. The auto setting comes after the minimum aperture.
  • Aperture diaphragm in Programmed and Shutter Priority exposure modes may make frequent noises with older lenses. In reality, all Fujifilm X-Mount lenses make frequent aperture diaphragm moves during use but native lenses and the latest adapted lenses taking advantage of Metabones' smooth iris feature can do so quietly without making noticeable tick noises.
  • IBIS is supported only with fixed focal length lenses at or below 100mm (after multiplying by 0.7x in the case of Speed Booster ULTRA). OIS will override IBIS. You cannot combine them. (fixed from firmware V1.10)
  • With IS/OS/VC lenses the IS MODE setting is ignored and both SHOOTING ONLY and CONTINUOUS modes behave in the same way which is similar to a Canon camera but different from what Fujifilm OIS lenses do. This is done to maximize IS effectiveness. A negative consequence of this is that there may be no OIS during focus check.




Unsupported List 

  • EF-S lens. EF-S lenses require modification to fit or may remain incompatible even after modification.
  • Lens correction such as peripheral shading, CA and distortion 
  • Focus confirmation "chip" (e.g. Dandelion)
  • M42 screw mount adapters (see note 4)
  • Stacking non-Metabones/non-Conurus mount adapters on top (see note 5 and list of lenses which require modification below.)


Speed Booster® ULTRA for X-mount, E-mount, EF-M mount and RF-mount cameras

Sharper corners, less distortion, reduced vignetting 

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. (More information can be found in the press release here)



Tested Cameras

  • Fujifilm X-A1
  • Fujifilm X-H1, X-H2, X-H2s
  • Fujifilm X-Pro1, X-Pro2, X-Pro3
  • Fujifilm X-T3, X-T4
  • Fujifilm X-T30
  • Fujifilm X-T100


Tested Lenses

    Smooth Iris
  Model Support
  Canon EF 40mm F/2.8 STM
  Canon EF 50mm F/1.2L USM  
  Canon EF 50mm F/1.4 USM  
  Canon EF 50mm F/1.8 II   
  Canon EF 50mm F/1.8 STM
  Canon EF 85mm F/1.2L II USM  
  Canon EF 100mm F/2.8 USM Macro  
  Canon EF 100mm F/2.8L IS USM Macro
  Canon EF 135mm F/2 L USM  
  Canon EF 200mm F/2.8L II USM  
  Canon EF 300mm F/2.8L IS II USM
  Canon EF 300mm F/4L IS USM  
  Canon EF 400mm F/5.6l  
  Canon EF 8-15mm F/4L Fisheye
  Canon EF 16-35mm f/2.8L II USM
  Canon EF 17-35mm F/2.8L USM  
  Canon EF 24-70mm F/2.8L II USM
  Canon EF 24-70mm F/2.8L USM Mk1  
  Canon EF 24-105mm F/4L IS USM  
  Canon EF 28-70mm F/3.5-4.5 II   
  Canon EF 28-135mm F/3.5-5.6 IS USM  
  Canon EF 28-80mm F/3.5-5.6 III USM  
  Canon EF 70-200mm F/2.8L IS II USM
  Canon EF 70-200mm F/4L IS II USM
  Canon EF 70-200mm F/4L USM  
  Canon EF 70-300mm F/4-5.6 L IS USM  
  Canon EF 100-400mm F/4.5-5.6 L IS II USM  
  Canon EF TS-E 17mm f/4L  
  Canon EF TS-E 24mm f/3.5L II  
  Sigma 24mm F/2.8 Super Wide II   
  Sigma 35mm F/1.4 DG Art 012
  Sigma 50mm F/1.4 DG HSM non art  
  Sigma 135mm F/1.8 DG HSM Art 017
  Sigma 24-35mm F/2 Art 015  
  Sigma 24-105mm F/4 OS HSM Art 013  
  Tamron 45mm F/1.8 VC (F013)  
  Tamron 10-24mm F/3.5-4.5 VC HLD (B023)  
  Tamron 15-30mm F/2.8 VC (A012)  
  Tamron 17-50mm F/2.8 VC (B005)  
  Tamron 18-250mm F/3.5-6.3 Di II (A18)  
  Tamron 18-270mm F/3.5-6.3 Di II VC (B003)  
  Tamron 18-270mm F/3.5-6.3 Di II VC PZD (B008)  
  Tamron 24-70mm F/2.8 Di VC USD (A007)  
  Tamron 28-300mm F/3.5-6.3 XR Di (A06)  
  Tamron 35-150mm F/2.8-4 Di VC OSD (A043)  
  Tamron 70-210mm F/4 Di VC USD (A034)  
  Tamron 70-300mm F/4-5.6 Di VC USD (A005)  
  Tokina 50mm F/1.4 Opera  
  Zeiss ZE 18mm F/3.5mm Distagon  
  Canon EF-Extender (Teleconverter)  


Note :

  • 1. EF-S lenses do not fit on Speed Booster®. Some EF-S lenses may be modified to fit, but do so at your own risk.
  • 2. Third-party lenses designed for APS-C format do not have enough coverage when used in conjunction with Speed Booster®.
  • 3. For use with fast lenses (faster than f/1.4), the pre-boost apertures will be displayed in the camera.

Slow lenses will report boosted apertures to the camera body but fast lenses will report pre-boost apertures. We won't show f/0.9 with a f/1.2 lens attached, but show f/1.2 instead.


a) EF 85/1.2L attached, camera display = f/1.2, physical aperture (lens + Speed Booster® combined) = f/0.85.

b) Sigma 35/1.4 attached, camera display = f/1.0, physical aperture (lens + Speed Booster® combined) = f/1.0.

  • 4. Some improperly-made M42 screw mount adapters may short the electronic contacts of the Speed Booster® and cause damage to the Speed Booster® and/or camera body.
  • 5. Many manual focus lenses (e.g. OM 28/2.8, OM 50/1.8, Leica R 15/3.5) have rear protrusions (spikes, levers, other appendages) which would damage the optics and/or housing of Speed Booster®  They need to be modified before they can be safely used on Speed Booster® Check and make sure there are no rear protrusions from the adapter/lens combination before using on Speed Booster®. Scratches and damages caused by rear protrusions on Speed Booster® are not covered by warranty.


List of manual focus lenses which REQUIRE MODIFICATION to be used on Speed Booster®

Many manual focus lenses have rear protrusions (spikes, levers, other appendages) which would damage the optics and/or housing of Speed Booster® They need to be modified before they can be safely used on Speed Booster® Check and make sure there are no rear protrusions from the adapter/lens combination before using on Speed Booster®. Scratches and damages caused by rear protrusions or by poor quality adapters are not covered by warranty. The following is an incomplete list of lenses known to be incompatible.

Leica R

Super-Elmar-R 15mm

Elmarit R 28/2.8

Elmarit R 35/2.8

Summicron R 50/2

Nikon F

20/2.8 AI-S

Olympus OM

OM 18/3.5

OM 21/2

OM 21/3.5

OM 28/2.8

OM 50/1.8

Pentax K

Every Pentax K-mount lens has a protruding fin and an aperture lever. It does NOT fit.





Why Metabones®?

Since its inception, Metabones has been designing and manufacturing lens adapters recognized among professionals and enthusiasts as leaders in design and workmanship.

Contrary to the popular trend of other factories using an aluminum ring painted black on the camera-body-side, we instead take no short-cut but use precision-machined brass with chromium plating on both the camera-body and the lens sides of our adapters, in order to ensure smooth mounting, great appearance, and durability. The lens side of the adapter features a strong leaf-spring structure, strengthening the adapter-lens connection and ensuring tightness of the lens in order to reduce wear and prevent focus errors and optical alignment issues from appearing.

Metabones uses matte-black treatment to keep internal reflection to a minimum in order to maintain the maximum optical quality possible with the lens.

All Metabones Adapters follow this tradition of uncompromising precision, robust build quality and outstanding finish. Our new Smart AdapterTM series of products add industry-leading electronic interfacing technology from Canada, with true electronic control of the lens' aperture directly from the camera body.


Our Smart AdapterTM  series adapters have the following additional features