|Features and Benefits||Limitations|
Always Enhance and Never Degrade the Performance of the Attached Master Lens
Like the ULTRA series for Sony E-mount, the new Speed Booster ULTRA m43 uses an advanced 5-element 4-group optical design incorporating ultra-high index tantalum-based optical glass. However, the new design is specifically optimized for the Micro Four Thirds sensor and filter stack, and as a result achieves an astonishing level of performance that sets a new standard for focal reducers.
Like the revolutionary original Metabones Speed Booster® announced in January 2013, the Speed Booster ULTRA m43 has a magnification of 0.71x, and so it effectively reduces the crop factor of mirrorless Micro Four Thirds mount cameras from 2.0x to 1.4x. However, the new ULTRA design makes very effective use of exotic materials at the furthest limit of glassmaking technology, and as a result is almost perfectly corrected for use with all fullframe SLR lenses regardless of aperture. The Speed Booster ULTRA m43 will also work extremely well with many DX and APS-C format lenses provided the image circle of the lens is large enough. Optical performance of the new Speed Boosters is so good that the MTF of any lens attached to it will be improved. Even the latest generation of ultra-high performance SLR lenses such as the Zeiss Otus series can be improved by adding a Speed Booster ULTRA m43. (More information can be found in the press release here and whitepaper here)
Autofocus with an Optimum Balance of Accuracy, Speed, Consistency and Reliability
New in Speed Booster ULTRA 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.
Select the correct EF-MFT Speed Booster for your camera
Autofocus Lens Compatibility List
The following table lists lenses which has been tested. Other lenses not listed here typically works well, too.
|Accurate||Tested by the community, thanks!||Accurate only on newer cameras such as Panasonic G7 and GX8|
|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 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 100mm f/2.8 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 18-35mm f/1.8 DC Art
Sigma 18-125mm f/3.8-5.6 DC HSM
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 DXII
|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 50mm f/1.8 II
Sigma 50mm f/1.4 EX HSM
Tamron 28-300mm f/3.5-6.3 XR Di VC A20
|Manual focus only||Not supported|
|Contax N lenses modified by Conurus
Tamron SP 17-50mm f/2.8 VC B005
Zeiss ZE lenses
|Focus confirmation „chips“|
Manual Focus Lens Compatibility
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.
Focus confirmation „chips“ such as Dandelion are incompatible.
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
Every Pentax K-mount lens has a protruding fin and an aperture lever. It does NOT fit.