Metabones Speed Booster Ultra - Canon EF to Micro Four Thirds

The Speed Booster Ultra from Metabones allows a Canon full-frame EF-mount lens to be mounted onto a Micro Four Thirds compact system camera. Like the previous Metabones Speed Booster model, the updated Ultra has a magnification of 0.71x so it effectively reduces the crop factor of mirrorless cameras with DX-sized sensors, such as Sony E-mount and Fuji X-mount cameras, from 1.5x to 1.07x. However, the new optical design in the Ultra uses 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.

Key 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
• Supports 16:9 video with DX lenses

Electronic

• 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
• 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 internal reflection
• Compatible with all MFT mount cameras, including GH4, OM-D, Blackmagic Cinema Camera, Blackmagic Pocket Cinema Camera and JVC GY-LS300

Limitations

• EF-S lenses require modification to fit (but third party DX lenses can be used without modification)
• Some EF-S and DX lenses may not have enough coverage of the entire image circle for stills after widening by 0.71x (but video will have enough coverage).
• No video AF for Olympus
• AFC (continuous AF) and AFF (flexible AF) modes are not supported
• Panasonic video AF may hunt more than a native lens or have unsatisfactory performance
• No support for Focus Stacking and Focus Bracketing on Olympus
• 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
• Iris changes are unsmooth but 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
• No support for in-camera correction such as peripheral shading, CA and distortion
• Designed to cover a 24mm image circle but not enough to cover Super35 so JVC GY-LS300 needs to have VSM configured to 86% (4k)