Viltrox · Canon EF → Canon RF adapter
Viltrox EF-EOS R5 (autofocus EF-to-RF) — Canon EF → Canon RF adapter
Third-party alternative to Canon's official EF-EOS R; significantly cheaper, similar AF behaviour on most EF lenses.
At a glance
- Vendor
- Viltrox
- Release year
- 2024
- Body-side contacts
- 12 pins
- Flags
- firmware-updatableweather-sealed —requires glass —
What this adapter preserves
Compatibility for Canon EF lens on a Canon RF body (computed from the lensmount dataset — open the Canon EF to Canon RF adapter page for the full verdict, flange clearance, and adapter caveats).
- Focus: Full AF
- IS: IS / IBIS preserved
- Aperture: Electronic aperture
- Infinity focus: Reaches infinity
What it does
Firmware-updatable via USB-C, which is uncommon for the price point.
Firmware history
Firmware history
- v1.00
- Initial release covering R5 / R6 / R6 Mark II + curated Canon EF lens list
- v1.10
- Refined AF performance with EF 70-200 f/2.8L IS III / EF 100-400 f/4.5-5.6L IS II
- EOS R3 / R5 specific tuning
Approximate milestones — verify against the Viltrox firmware page for the authoritative changelog.
Specific lens compatibility
Per-lens notes for the Viltrox EF-EOS R5 (autofocus EF-to-RF) based on the vendor's published compatibility chart and community-tested behaviour. Three states: works (✓) — full AF / IS / aperture behave as native; partial (⚠) — usable with a documented caveat; issue (✗) — known incompatibility or rough edge.
| Lens | Status | Note |
|---|---|---|
| Canon EF 24-105 mm f/4L IS II USM | Works | Full AF + IS pass-through on R5 / R6 Mark II. One of the smoothest EF zooms on this adapter. |
| Canon EF 70-200 mm f/2.8L IS III USM | Works | v1.10 firmware refined AF behaviour specifically for this lens — continuous-AF tracking on R3 / R5 is on par with Canon's own adapter. |
| Sigma 150-600 mm f/5-6.3 DG OS HSM Contemporary (EF) | Partial | AF acquires reliably for static subjects, but continuous-AF tracking on R5 lags Canon's own EF-EOS R adapter perceptibly. OS pass-through is fine. |
Common questions
- How does the Viltrox EF-EOS R5 compare to Canon's official adapter?
- About one-third the price with similar AF behaviour on most EF lenses. Canon's original is better-built, weather-sealed, and offered in Control Ring / Drop-In Filter variants Viltrox doesn't ship.
- Does it support EF-S lenses on a full-frame RF body?
- Yes — the RF body's auto-engaged 1.6× APS-C crop mode triggers when an EF-S lens mounts, exactly as with Canon's own EF-EOS R adapter.
- Can I update its firmware?
- Yes via the USB-C port on the side of the adapter — uncommon at this price point. Viltrox publishes signed firmware files on viltroxstore.com.
Head-to-head comparisons
Mounts on either side
Other adapters worth comparing
More from Viltrox
Same lens-side mount (Canon EF)
- Canon EF-EOS R — onto Canon RF · 2018
- Sigma MC-11 — onto Sony E · 2016
- Sigma MC-21 — onto L-Mount · 2019
- Metabones EF-E Mark V — onto Sony E · 2017
- Metabones Speed Booster ULTRA 0.71× EF-E — onto Sony E · 2014
- Viltrox EF-NEX IV (EF-E) — onto Sony E · 2018
- Fringer EF-FX Pro II — onto Fujifilm X · 2020
- Fringer EF-GFX Pro — onto Fujifilm GFX · 2019
- Canon EF-EOS M — onto Canon EF-M · 2012
- Fotodiox Pro EF-NEX — onto Sony E · 2018
- Kipon Baveyes EF-FE 0.7x — onto Sony E · 2017
- Kipon Baveyes EF-FX 0.7x — onto Fujifilm X · 2017
- Commlite CM-EF-NEX HS — onto Sony E · 2018
- Commlite CM-EF-EOS R — onto Canon RF · 2019
- Viltrox EF-M2 II — onto Micro Four Thirds · 2018
- Fotodiox Vizelex ND Throttle EF-NEX — onto Sony E · 2014
- Fringer EF-NZ II — onto Nikon Z · 2023
Same body-side mount (Canon RF)
- Canon EF-EOS R — from Canon EF · 2018
- K&F Concept M42-EOS R Pro — from M42 · 2020
- Novoflex EOSR/LEM — from Leica M · 2019
- Commlite CM-EF-EOS R — from Canon EF · 2019
- Fotodiox FD-RF — from Canon FD · 2019
Keep exploring
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