A new Micro-4/3 mount Speed Booster^® adapter designed exclusively for the Panasonic GH4 and other selected Micro Four Thirds cameras (refer to the below camera compatbility table), with a magnification of 0.64x.  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. The new Speed Booster XL 0.64x 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.  When the GH4 is used in Cinema 4k video mode the horizontal full frame crop factor is reduced from 2.34x to 1.50x, thus effectively transforming the GH4 into a super-35 format 4k cine camera.  In addition, the speed of any attached lens is increased by 1¹/₃ 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. (More information can be found in the press release here ) Key Features

• Increase maximum aperture by 1¹/₃ stops
• Increase MTF.
• Makes lens 0.64x wider.
• Build-in electronics to control lens aperture.
• The lens aperture is set by the controls on the camera body.
• Powered by camera body. no external power source required. 
• High performance 32-bit processor and efficient switched-mode power supply.
• The interior is painted with flocking coating to further reduce the internal reflection. 
• The tripod foot is detachable and compatible with Arca Swiss, Markins and Photo Clam ball heads.
• Support Panasonic GH4, GH3, G3, G5, G6, G10, GF3, GF5, GF6, GX1, Olympus E-PL7, Blackmagic Cinema Camera with Micro Four Thirds mount**, Blackmagic Pocket Cinema Camera***

Optics designed by Caldwell Photographic in the USA (patent pending). 

CompatibilityThe Speed Booster XL 0.64x is similar to the Blackmagic-specific 0.64x BMCC Speed Booster (MB_SPEF-BMCC-BM1), but has been completely re-designed to meet the following requirements: 

• The working distance has increased by 1mm to permit use on the Panasonic GH4 and a number of other Micro Four Thirds cameras without touching the flexible outer cover of the camera’s shutter mechanism.
   
• The optics are optimized for a standard Micro Four Thirds filter stack thickness of 4mm rather than the 2.4mm found in Blackmagic cameras.
   
• The image circle diameter has been increased to 21.63mm so that the full 17.3mm x 13mm Four Thirds format is covered.  This has been achieved while maintaining unusually high image quality over the 17.4mm image circle used by the Panasonic GH4 in its Cinema 4k video mode.

 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.

 

 

 

*Not yet tested

---

Metabones Speed Booster XL 0.64x Specifications:Magnification:  0.64xCrop Factor for Full Micro Four Thirds format:  1.28xCrop Factor with GH4 in Cinema 4k (4096 x 2160) Video Mode:  1.5xMaximum Output Aperture:  f/0.80 (with f/1.2 lens attached)Rectilinear Distortion:  < 0.8%Lens Elements/Groups:  6/4Length Reduction:  6.2 mmCamera Mount:  Micro Four ThirdsImage Format:  17.3 mm x 13.0 mm (full Micro Four Thirds format)

---

 

Supported

Not supported

EF lensesImage stabilization (IS) lensesElectronic 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 (see note 1)Contax N mount lenses modified to Canon EF by Conurus (see note 2)Contax 645 NAM-1 adapter modified to Canon EF by Conurus (see note 2)Sigma, Tamron and Tokina lenses in Canon EF mount (see note 2)External 5 Volt power supply (see note 6)

AutofocusEF-S lenses (some EF-S lenses may need modification)Lens correction such as peripheral shading, CA and distortionFocus 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.)Lens: Tamron SP 17-50mm F/2.8 XR Di II VC

Note:

1. Requires lenses supporting distance information.
2. A third party zoom lens may need to be registered with the Speed Booster/Smart Adapter first in order to detect its maximum aperture. 
3. This Smart Adapter is designed to cover an 17.3mm x 13mm sensor.
4. Some improperly-made M42 screw mount adapters may short the electronic contacts of the Smart Adapter and cause damage to the Smart Adapter 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 Smart Adapter^. They need to be modified before they can be safely used on Smart Adapter. Check and make sure there are no rear protrusions from the adapter/lens combination before using on Smart Adapter. Scratches and damages caused by rear protrusions on Smart Adapter are not covered by warranty.
6. For those passive (without electronic pin or without power supply from the camcorder) MFT camcorders, this Speed Booster Adapter can also be powered by external third-party 5 Volt MicroUSB power supply*.
   * ) third-party 5 Volt MicroUSB power supply is not provided in the box. The compatibility of 3rd party power supply can't be guaranteed. 
7. For use with fast lenses (faster than f/1.8), 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/0.8(Speed Booster XL Max. limit) with a f/1.2 lens attached, but show f/1.2 instead. Example:a) EF 85/1.2L attached, camera display = f/1.2, physical aperture  (lens + Speed Booster combined) = f/0.8 (Speed Booster XL Max. limit).
   b) Sigma 18-35/1.8 attached, camera display = f/1.0, physical aperture (lens + Speed Booster combined) = f/1.0.

---

Select the correct EF-MFT Speed Booster fits for your camera:

 

List of lenses (have been tested by metabones) with support on EF-M43 Smart Adapter. (Lenses which have been tested with EF-E Smart Adapter may refer to EF-E Smart Adapter product page.)

Canon EF zooms Canon 20-35mm3.5-4.5Canon 28-80mm2.8-4LCanon 70-200mm2.8LCanon 24-70mm2.8_IICanon 24-105mm4_LCanon 70-200mm4_LCanon 70-300mm4-5.6LCanon 70-300mm4-5.6	Canon EF primes Canon 50mm1.8Canon 50mm1.4Canon 85mm 1.2Canon 100mm 2.8
Others Sigma 18-200mm3.5-6.3Zeiss 35mm2