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Metabones EF-E mount T Speed Booster ULTRA ( 0.71x) Adapter with Support Foot for Canon EF-Mount Lens to Sony E-Mount (MB_SPEF-E-BT2)

Model #372805
  • $208.00

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New in box complete with manufacturer's USA warranty. Not previously owned or used.
Essentially new with no signs of use. “Open box.” In manufacturer's packaging with original accessories and instructions. 180-day warranty.
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Noticeably used with average signs of wear. Shows moderate wear for the age of the item, with the possibility of blemishes and/or minimal dings. Lens glass may have average dust and zoom/focus ring tension may have slight looseness or tightness overall, but will not affect picture quality. Accessories usually not included, unless noted in listing. 180-day warranty.
Frequently used with above-average wear. May have dents, dings, or finish loss. Lens glass may have small scratches, dust, and blemishes, and zoom/focus ring tension may have moderate looseness or tightness overall, but should not affect picture quality. Accessories usually not included, unless noted in listing. 180-day warranty.
Heavily used with extensive visible wear. Equipment is rough, with multiple impressions in the finish, excessive finish loss and brassing. Glass will have marks, fungus and/or heavy/cloudy haze which could affect picture quality. Accessories usually not included, unless noted in listing. Not covered under KEH warranty.
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$208.00
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Metabones Speed Booster ULTRA 0.71x: Canon EF glass, Sony E-Mount reach

Canon EF and EF-S lenses mount directly onto Sony E-Mount bodies through this adapter, and the optics inside do more than pass light, they compress the image circle by 0.71x, which translates to a 1.33-stop gain in maximum aperture. A 50mm f/1.4 Canon lens becomes an effective 35.5mm f/1.0 equivalent on an APS-C Sony body. That is not a marketing claim; it is geometry built into the Speed Booster ULTRA optical formula.

The adapter maintains full electronic communication between lens and camera, passing EXIF data and supporting aperture control through the body. The included support foot matters practically: heavier Canon L-series zooms need that physical stability point to avoid stressing the mount over time, and it makes the rig balance better on a shoulder or cage setup.

For Sony APS-C shooters in particular, the 0.71x reduction partially compensates for the crop factor, recovering field of view closer to what those EF lenses were designed to deliver. Someone who already owns a Canon EF kit has a real path into Sony E-Mount bodies without abandoning glass they know.

Who It's For

Cinematographers and video shooters working on Sony APS-C or full-frame E-Mount cameras who own Canon EF glass benefit directly from the 1.33-stop aperture increase, which matters in low-light run-and-gun work. Documentary photographers transitioning from Canon DSLRs to Sony mirrorless keep their existing Canon EF and EF-S lenses functional with full electronic communication intact. Travel and street photographers shooting Sony APS-C bodies gain field of view back from the crop factor through the 0.71x focal reduction, making wider Canon EF primes behave closer to their full-frame intent.

Key Features

  • Canon EF to Sony E-Mount conversion with full electronic communication
  • 0.71x focal length reduction with 1.33-stop aperture gain
  • Speed Booster ULTRA optics preserve image quality and brightness
  • Included support foot stabilizes heavier lens assemblies
  • EXIF data transmission and aperture control supported
  • Compatible with Canon EF and EF-S lenses

FAQ

Does this adapter work with both Canon EF and EF-S lenses?
Yes. The adapter accepts Canon EF and EF-S lenses on the input side and mounts to Sony E-Mount cameras on the output side.
What does the 0.71x magnification actually do?
It compresses the image circle, which reduces the effective focal length of your lens and increases its maximum aperture by 1.33 stops. A 50mm f/1.4 EF lens becomes 35.5mm f/1.0 equivalent on Sony APS-C.
Will autofocus and aperture control work through the adapter?
Yes. The adapter maintains full electronic communication between the lens and camera body, passing EXIF data and supporting aperture control via the body.
What is the support foot for?
It provides a physical stability point for heavier Canon L-series zooms to prevent mounting stress and improves balance when the rig is shoulder-mounted or on a cage.
Can I use this on both Sony full-frame and APS-C cameras?
Yes. The adapter is designed for Sony E-Mount full-frame and APS-C bodies, though the 0.71x reduction is particularly useful on APS-C to partially compensate for crop factor.
Does autofocus speed change with this adapter?
The specs do not detail autofocus performance changes. Autofocus function is supported, but speed may vary depending on the lens and camera combination.
SpecificationValue
MountCanon EF to Sony E-Mount
Mount InputCanon EF
Mount OutputSony E-Mount
Magnification0.71x
Aperture Increase+1.33 stops

This description was generated using AI based on KEH's internal product standards, product expertise, and knowing what customers care about most. While we strive for accuracy, details may vary by individual item.

Brand Name Metabones
Lens Mount Sony E Mount