Metabones EF - MFT T Speed Booster ULTRA 0.71x II (MB_SPEF-M43-BT4)

Metabones EF - MFT T Speed Booster ULTRA 0.71x II (MB_SPEF-M43-BT4)

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.

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 on Panasonic camera bodies, subject to certain limitations. 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, which is significantly faster than a DSLR Four Thirds lens on a Panasonic Micro Four Thirds camera (with adapter), or our E-mount offerings on Sony cameras prior to Alpha 7R II.

Features:

Optical
– Increase maximum aperture by 1 stop
– Increase MTF of any lens attached
– Makes lens 0.71x wider
– Patented 5-element/4-group optical design incorporating ultra-high index tanatalum-based optical glass by Caldwell Photographic in the USA

Electronic
– Auto focus on Panasonic Mirco Four Thirds cameras
– Can be powered either by camera body or by third-party external 5V power source (not included)
– Iris/aperture controlled by the camera body.
– Image stabilization (IS) lens support
– 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)

Other
– Detachable tripod foot compatible with Arca Swiss, Markins and Photo Clam ball heads.
– Flocking material coating to reduce the internal reflection.

Limitations
– EF-S lenses require modification to fit (but third party DX lenses can be used without modification)
– No autofocus support for JVC and Olympus
– AFC (continuous AF) and AFF (flexible AF) modes are not supported
– No 24p video AF
– Video AF may hunt more than a native lens
– No support for in-camera correction such as peripheral shading, CA and distortion
– Designed to cover an 17.3mm x 13mm sensor but not enough to cover Super35 so JVC GY-LS300 needs to have VSM configured to 80%

Autofocus Lens Compatibility List

Accurate
Canon EF20-35mm f/3.5-4.5 USM
Canon EF24-105mm f/4L IS USM
Canon EF35-80mm f/4-5.6
Canon EF40mm f/2.8 STM
Canon EF50mm f/1.2L USM
Canon EF50mm f/1.4 USM
Canon EF70-200mm f/2.8L IS II USM
Canon EF70-300mm f/4-5.6L IS USM
Canon EF85mm f/1.2L II USM
Canon EF100mm f/2.8 USM macro
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

Accurate only on newer cameras such as Panasonic G7
Canon EF70-200mm f/4L USM
Canon EF135mm f/2L USM
Canon EF200mm f/2.8L II USM

Inaccurate
Canon EF50mm f/1.8 II
Sigma 50mm f/1.4 EX HSM

Manual focus only
Contax N lenses modified by Conurus
Tamron SP 17-50mm f/2.8 VC B005
Zeiss ZE lenses

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

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.