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Metabones EF Lens to Micro Four Thirds T Speed Booster XL 0.64x

Code: BLO/MB-122
The Speed Booster XL 0.64x uses an advanced 6-element optical design to achieve extraordinary optical performance at apertures up to an incredible f/0.80, a new record for Micro Four Thirds format. Designed for selected Micro Four Thirds cameras, it reduces the full-frame crop factor of the Panasonic GH4 from 2.0x to 1.28x, thus effectively transforming these cameras into APS-H format. This adapter is designed for full frame lenses, for compatible APS-C lenses see here


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The Speed Booster XL 0.64x uses an advanced 6-element optical design, with a magnification of 0.64x, to achieve extraordinary optical performance at apertures up to an incredible f/0.80, a new record for Micro Four Thirds format. Designed for the Panasonic GH4 and other selected Micro Four Thirds cameras, it reduces the full-frame crop factor of the Panasonic GH4 from 2.0x to 1.28x, thus effectively transforming these cameras into APS-H format


Like all Metabones Speed Boosters, the Speed Booster XL 0.64x is optimised to fully account for a camera’s filter stack located near the sensor surface4. This is especially critical at the extremely large apertures made possible by Speed Booster technology. As a result of this careful optimisation, an enormous range of full-frame optics, ranging from vintage film lenses to the latest digital designs, will function flawlessly when adapted to compatible Micro Four Thirds camera bodies. In fact, most lenses will have significantly improved MTF when used with the Speed Booster, compared to using them with a plain (i.e. “glassless”) adapter on Micro Four Thirds cameras.


In addition, the speed of any attached lens is increased by 1 1/3 stops, with a maximum output aperture of f/0.80 when an f/1.2 lens is used. For example, a 50mm f/1.2 becomes a 32mm f/0.80, which is the fastest aperture available for full size Micro Four Thirds format. Perhaps most exciting of all, in addition to increasing lens speed and field of view, the Speed Booster XL 0.64x offers amazingly high image quality even at extremely large apertures.


New in Speed Booster XL for Canon EF Mount to Micro Four Thirds is autofocus support, subject to certain limitations (see table above for details). We are pleased to report that Panasonic Micro Four Thirds camera bodies are capable of autofocusing accurately even if the maximum aperture of the Speed Booster and the lens combined is in the sub-f/1.0 range. Although our first and foremost priority is accuracy, we are able to make great strides in autofocus speed as well.

Features and benefits



  • Increase maximum aperture by 11/3 stop
  • Increase MTF
  • Makes lens 0.64x wider
  • Patented 6-element/4-group optical design by Caldwell Photographic in the USA
  • Supports 4k video mode with DX lenses (except on GH5).
  • Autofocus
  • Can be powered either by camera body or by third-party external 5V power source (not included)
  • Iris/aperture controlled by the camera body
  • Smooth iris support with the latest Canon (2009+), Tamron (SP series 2013+) and Sigma (2016+) lenses
  • Image stabilization (IS) lens support
  • Support for cameras with in-body image stabilization (IBIS), including Panasonic GX7, GX8, GX80/85 and Olympus cameras
  • Electronic manual focusing (e.g. EF 85/1.2L II and discontinued EF 50/1.0L)
  • EXIF (focal length, aperture, zoom range)
  • Distance and zoom display on camcorders (requires lenses supporting distance information)
  • Canon Cinema EOS lens (CN-E Compact-Servo) support, including AF (requires external 5V power through micro USB port), auto iris and servo zoom
  • Detachable tripod foot compatible with Arca Swiss, Markins and Photo Clam ball heads.
  • The opening is flocked with felt material to reduce internal reflection.
  • Supports only Panasonic GH5, GH4, GH3, G3, G5, G6, G7, G10, GF3, GF5, GF6, GX1, GX8, GX80/GX85, Olympus E-PL7, PEN-F, Blackmagic Cinema Camera with Micro Four Thirds mount**, Pocket Cinema Camera*** and Micro Cinema Camera***
  • EF-S lenses require modification to fit or may remain incompatible even after modification (but third-party DX lenses can be used without modification)
  • On GH5, Speed Booster XL can be used with full frame lenses only. DX lenses are unable to cover full-sensor-width readout + in-body image stabilizer (IBIS)
  • EF-S and third-party DX lenses do not cover the full Micro Four Thirds sensor in still photo and FHD video (but will cover 4k video mode on GH4, GX8 and GX80/85).
  • No video AF for Olympus
  • AF may not work if the maximum aperture of the lens plus any EF Extender or other teleconverter attached is smaller than f/8 before boost or smaller than f/5.1 after boost.
  • AFC (continuous AF) and AFF (flexible AF) modes are not supported, except on Olympus OM-D E-M1.
  • Panasonic video AF may hunt more than a native lens or have unsatisfactory performance.
  • Some Tamron lenses may have unsatisfactory AF accuracy.
  • No support for Focus Stacking and Focus Bracketing on Olympus.
  • On Olympus, other than E-M1, you may move the single AF point among any of the 81, but you may not multi-point AF. There is no restriction on E-M1 and Panasonic.
  • Very early Olympus models (e.g. E-PL1) have no autofocus support.
  • EF-mount lenses are not silent but may make audible click noises during autofocus operation and iris changes which may be picked up by the built-in microphone of the camera. An external microphone is recommended for video.
  • Use of Canon Cinema Compact-Servo lenses such as CN-E 18-80mm T4.4 L KAS S for still photography is not supported.
  • Iris changes are in 1/8 stop steps which may be noticeable in video recordings. Programmed exposure mode and shutter priority exposure mode should not be used for video. This limitation does not apply to Cinema EOS lenses which permit fine resolution iris control, such as CN-E 18-80mm T4.4 L IS KAS S.
  • No support for in-camera correction such as peripheral shading, CA and distortion


Magnification: 0.64x
Crop Factor for Full Micro Four Thirds format: 1.28x
Crop Factor with GH4 in Cinema 4k (4096 x 2160) Video Mode: 1.5x
Maximum Output Aperture: f/0.80 (with f/1.2 lens attached)
Rectilinear Distortion: < 0.8%
Lens Elements/Groups: 6/4
Length Reduction: 6.2 mm
Camera Mount: Micro Four Thirds
Image Format: 17.3 mm x 13.0 mm (full Micro Four Thirds format)

Lens compatibility chart

Accurate Tested by Metabones community Accurate only on newer cameras such as Panasonic G7, GX8 and GX80/85
  • Canon CN-E 18-80mm T4.4 Compact-Servo EF**
  • Canon CN-E 70-200mm T4.4 Compact-Servo EF**
  • Canon EF 8-15mm f/4L USM Fisheye*
  • Canon EF 20-35mm f/3.5-4.5 USM
  • Canon EF 24-105mm f/4L IS USM
  • Canon EF 28-80mm f/3.5-5.6 II
  • Canon EF 35-80mm f/4-5.6
  • 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 STM*
  • Canon EF 70-200mm f/2.8L IS II USM*
  • Canon EF 70-300mm f/4-5.6L IS USM*
  • Canon EF 85mm f/1.2L II USM
  • Canon EF 100mm f/2.8L IS Macro USM*
  • Canon EF 100-400mm f/4.5-5.6L IS USM
  • Canon EF 100-400mm f/4.5-5.6L IS II USM*
  • Canon EF Extender 1.4x III
  • Canon EF Extender 2x
  • Sigma 18-125mm f/3.8-5.6 DC HSM
  • Sigma 24-105mm f/4 Art
  • Tokina AT-X PRO 11-16mm f/2.8 DX II
  • Canon EF 70-200mm f/2.8L IS USM (Mark I)
  • Canon EF 85mm f/1.2L USM (Mark I)
  • Canon EF 200mm f/2.0L IS USM
  • Canon EF 300mm f/2.8L IS USM (Mark I)
  • Canon EF 400/2.8L IS USM (Mark I)
  • Canon EF 70-200mm f/4L USM (non-IS)
  • Canon EF 135mm f/2L USM
  • Canon EF 200mm f/2.8L II USM
  • Canon EF 300mm f/4L IS USM
  • Canon EF 400mm f/5.6L USM
  • Sigma 18-35mm f/1.8 DC Art
  • Sigma 50-100mm f/1.8 DC HSM Art 016*
  • Tamron SP 15-30mm f/2.8 VC USD A012*
  • Tamron SP 45mm f/1.8 VC USD F013*
Inaccurate Require external USB power supply owing to high current consumption; AF inaccurate


  • Canon EF 50mm f/1.8 II
  • Canon EF 100mm f/2.8 Macro USM
  • Sigma 50mm f/1.4 EX HSM
  • Tamron 18-250mm f/3.5-6.3 Di II Macro A18
  • Tamron SP 24-70mm f/2.8 Di VC USD A007
  • Tamron SP 70-200mm f/2.8 Di VC USD A009*
  • Tokina AT-X PRO 11-16mm f/2.8 DX (I)
  • Tamron 28-300mm f/3.5-6.3 XR Di VC A20 (note 1)
  • Tamron 150-600/5-6.3 VC USD A011*
Does not fit, even after modification Manual focus only Not supported
  • Canon EF-S 18-135mm f/3.5-5.6 IS Nano USM
    • Contax N lenses modified by Conurus
    • Tamron SP 17-50mm f/2.8 VC B005
    • Zeiss ZE lenses
    • Focus confirmation "chips"
    * with smooth iris support ** CN-E Compact-Servo lens with some of MFT cameras may require external power to autofocus

    Camera Body Compatibility List

    Although the Speed Booster XL 0.64x has extra clearance compared to the 0.64x BMCC Speed Booster, there are still a number of Micro Four Thirds cameras that are not supported due to mechanical clearance issues. This is summarized in the table below, which is color-coded so that Green means the camera is supported and Red means the camera is not supported.

    Note that many of the Red-coded cameras actually do function, but there is a minor interference with the protective shutter cover. Although slight contact with the shutter cover appears to have no effect on the functioning or cosmetics of either the camera or the Speed Booster we cannot support these combinations due to possible risk of damage.

    Blackmagic Cinema Camera Pocket Cinema Camera Micro Cinema Camera (HD) Micro Studio Camera (4K)        
    JVC GY-LS300              
    Olympus E-M5 E-M1 E-M10 E-M5 II E-M1 II      
    E-P1 E-P2 E-P3 E-P5        
    E-PL1 E-PL2 E-PL3 E-PL5 E-PL6 E-PL7    
    E-PM1 E-PM2            
    Panasonic AF100              
    GH1 GH2 GH3 GH4 GH5      
    G1 G2 G3 G5 G6 G7 G10  
    GF1 GF2 GF3 GF5 GF6 GF7 GF8 GF800/850/9
    GX1 GX7 GX8 GX80/85        
    GM1 GM5