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

The Metabones Speed Booster ULTRA is a 0.71x adapter that lets you mount Canon EF lenses onto Sony E-mount cameras while condensing the image circle to increase light transmission by roughly one stop and widen the field of view. This version includes a support foot for better balance with heavier lenses. The Speed Booster ULTRA sits at the top of Metabones' adapter lineup, offering advanced optical correction and electronic communication between lens and body for autofocus and aperture control.

This adapter is aimed squarely at hybrid shooters and filmmakers who already own Canon glass and want to maximize its performance on Sony mirrorless bodies. The 0.71x factor effectively turns full-frame EF lenses into slightly wider, faster optics on APS-C Sony cameras, and the support foot helps distribute weight when using telephoto or larger glass. At this price point, especially in used condition, it offers a practical bridge for those unwilling to reinvest in native E-mount glass.