Top Pick: Metabones EF-X Mount T Speed Booster ULTRA 0.71x II+
A Speed Booster adapter is a focal reducer that concentrates the image circle from a full-frame lens onto a smaller crop sensor, shrinking the effective focal length while increasing the lens’s effective brightness so that APS-C cameras can deliver framing and light-gathering closer to full-frame setups. For most Fujifilm X shooters, the clear winner is the Metabones EF-X mount T Speed Booster ULTRA 0.71x II+. It cuts the usual 1.5x crop factor down to 1.07x, turning your X-T or X-H body into a near full-frame camera in how it frames and handles depth of field. At the same time, it makes your lens roughly one stop brighter, so a 50mm f/1.2 behaves like a 35.5mm f/0.9. This adapter is for photographers who own Canon EF glass or plan to buy used EF lenses and want the richest mix of focal lengths and ultra-fast apertures without abandoning APS-C. According to Metabones, there are 307 distinct Canon EF lenses versus 159 Fujifilm X lenses, with 42 EF lenses at f/1.4 or faster.
The EF-X mount T Speed Booster ULTRA 0.71x II+ also brings TruePDAF autofocus, which uses an internal lens profile database to drive phase detection rather than fallback contrast hunting. That is the real upgrade over older Metabones hardware: adapted EF lenses now focus far more like native glass, especially in low-contrast scenes where adapters used to struggle badly. You still need a modern body such as the X-H series, X-Pro2, or X-T2 and later to get full TruePDAF support. In-body stabilisation behaviour is improved, and the interior is flocked to tame reflections, which matters when you are concentrating light so aggressively in a focal reducer. The trade-offs are clear: you add bulk, you spend on the adapter and lenses, and native X-mount lenses will still autofocus better and weigh less overall. But if you want a crop sensor full frame experience and already have EF glass from a DSLR, this is the adapter to buy.
Smart Adapter II+: When You Want Reach More Than Speed
If you care more about keeping your telephoto reach than chasing a full-frame look, step down to the Metabones EF-X mount T Smart Adapter II+. Where the Speed Booster adapter bends light and changes your effective focal length and aperture, the Smart Adapter is an optically empty tube that passes through all electronic communication without altering how your lens behaves. Your 50mm stays a 50mm, and the familiar 1.5x crop factor remains in place. This makes the Smart Adapter II+ the better choice for wildlife, sports, or anyone who relies on the extra reach of an APS-C body and does not want their 70–200mm reframed into something more like a 50–142mm equivalent. You still gain access to the same large EF catalog, including many budget-friendly telephotos and specialty lenses that do not exist natively for Fujifilm X.
Crucially, the EF-X mount T Smart Adapter II+ also supports TruePDAF autofocus on compatible bodies, using the same lens profile database to drive phase detection instead of falling back to contrast detection. This means adapted lens autofocus feels far more reliable than with older generation adapters, especially in low-contrast scenes. Pros are clear: you keep the usefulness of the crop sensor for distant subjects, retain electronic aperture and autofocus with your EF lenses, and avoid the changes in framing that a focal reducer brings. The cons are just as real: you do not gain extra light, your APS-C camera still behaves like a crop sensor rather than a crop sensor full frame hybrid, and adapter-based autofocus never quite matches native X-mount lenses for speed or consistency. Still, for telephoto-minded shooters with EF glass, this Smart Adapter is the practical, no-drama choice.
| Spec | Speed Booster ULTRA 0.71x II+ | Smart Adapter II+ |
|---|---|---|
| Optics | Focal reducer with glass elements | No optics, electronic tube only |
| Crop factor effect | Reduces 1.5x to 1.07x for near full-frame framing | Leaves 1.5x crop unchanged |
| Light transmission | Approximately one stop brighter than native lens rating | No change in brightness |
| Best for | Wide and standard lenses, video, fast-aperture portrait work on APS-C | Telephoto, wildlife, sports where reach matters more than speed |
CINE Versions: Locking in EF Glass for Video and Hybrid Shooters
Metabones offers CINE versions of both the Speed Booster ULTRA 0.71x II+ and Smart Adapter II+ for Fujifilm X shooters who treat their cameras as serious video tools. The EF-X mount T CINE Speed Booster ULTRA 0.71x II+ and EF-X mount T CINE Smart Adapter II+ share the same optical and electronic guts as their standard counterparts, but add a robust clamping lock and slightly revised bodies that are built to hold heavier lenses securely on rigs. If you shoot wide or shoot video, this wider framing reads completely differently; the Speed Booster version can turn an X-H2 into a near full-frame cinema camera using EF zooms and primes you already own. The CINE Smart Adapter, meanwhile, suits operators who value the crop sensor’s extra reach with telephoto zooms while still wanting reliable lens adapter autofocus for run-and-gun shoots.
For hybrid shooters who bounce between gimbals, cages, and stills work, the CINE models are worth prioritising. The locking mechanism reduces wobble and gives more confidence when pulling focus or moving quickly with heavier EF lenses attached. You still get TruePDAF autofocus support on approved bodies, so adapted EF glass behaves far better than older Mark I adapters, which have hit their ceiling and cannot gain further autofocus improvements. The trade-offs mirror the standard versions: more mass at the mount, autofocus that remains a compromise compared with native X lenses, and the need to own or buy into the EF ecosystem for the whole setup to make sense. If your work is video-first or rig-heavy, however, the CINE Speed Booster and CINE Smart Adapter are the dependable way to build a flexible EF-to-Fujifilm X system that can cover everything from wide cine zooms to long telephotos.
An Alternative Path: Native Telephoto Like Viltrox 75mm f/1.8 Evo
Before you commit to EF adapters, it is worth contrasting them with a strong native APS-C option like the Viltrox 75mm f/1.8 Evo. On an APS-C body, this lens gives a 112.5mm full-frame equivalent field of view, a sweet spot for portraits when you want more background compression than a typical 56mm f/1.2 but find a 135mm equivalent too tight for real rooms. It weighs about 325 g and stays sharp from corner to corner even wide open, with only a small bump at f/2.8 and no real improvement beyond that. Vignetting fades by f/4 and chromatic aberration is effectively absent, even against the sun. The build relies on metal and high-quality plastics, with a metal mount and gasket and an aperture ring, though the Fujifilm version skips some features that Sony and Nikon versions include.
The Viltrox 75mm f/1.8 Evo’s bokeh is smooth and pleasant, only occasionally nervous against very busy backgrounds, and the lens holds performance well up to around f/8 before diffraction becomes noticeable at smaller apertures like f/11 and f/16. Flare and ghosting are the main complaints, with some loss of contrast if the sun hits at specific angles. Autofocus is the part that needs an asterisk: single-shot AF works reliably on Fujifilm bodies with subjects that are not charging toward the camera, but continuous AF on fast-moving subjects sees more misses, an issue that appears across Sigma, Fujifilm, and Viltrox lenses on the X-E5 and seems tied to autofocus algorithms rather than this lens’s motor. On a different mirrorless body, the same lens delivers far more consistent AF. For many APS-C shooters, a native lens like this paired with a small body gives a practical middle ground for portraits, concerts, and everyday shooting without adding adapter complexity.
Buy if / Skip if
- Buy the Metabones EF-X mount T Speed Booster ULTRA 0.71x II+ if you want your Fujifilm APS-C body to deliver near full-frame framing and an extra stop of light from fast EF primes.
- Skip the Metabones EF-X mount T Speed Booster ULTRA 0.71x II+ if telephoto reach is more important than a crop sensor full frame look, because the focal reducer shortens effective focal lengths.
- Buy the Metabones EF-X mount T Smart Adapter II+ if you own Canon EF telephotos and want to keep the 1.5x crop factor’s reach while gaining reliable lens adapter autofocus with TruePDAF support.
- Skip the Metabones EF-X mount T Smart Adapter II+ if you do not already own EF glass, since native X-mount lenses will generally autofocus better, weigh less, and avoid adapter compromise.
- Buy the Metabones CINE Speed Booster ULTRA 0.71x II+ if you shoot video on rigs and need a locking mount plus near full-frame coverage from EF cine zooms and primes.
- Skip the Metabones CINE adapters if you rarely shoot video or rig your camera, as the extra bulk and locking hardware add little for casual stills work.
- Buy the Viltrox 75mm f/1.8 Evo if you want a native APS-C portrait lens with sharpness wide open, pleasant bokeh, and a practical 112.5mm full-frame equivalent field of view.
- Skip the Viltrox 75mm f/1.8 Evo if you rely heavily on continuous autofocus for fast-moving subjects on Fujifilm, because AF performance in that mode is less consistent and flare can reduce contrast.
- Buy the Metabones ecosystem overall if you already own EF lenses from a DSLR you have moved on from and want to reuse them on Fujifilm X with improved autofocus and, with the Speed Booster, near full-frame behaviour.
- Skip the Metabones ecosystem if you prefer a simpler, lighter kit with fewer compromises, in which case building around high-quality native APS-C lenses like the Viltrox 75mm f/1.8 Evo may suit you better.
