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Commlite · Canon EFCanon RF adapter

Commlite CM-EF-EOS R Canon EFCanon RF adapter

Third-party EF → Canon RF adapter at ~50% the price of Canon's first-party EF-EOS R. Preserves AF / IS / electronic aperture on every EF / EF-S Canon and Sigma DG / Tamron Di USM / STM lens; USB-C firmware updatable.

At a glance

Vendor
Commlite
Release year
2019
Body-side contacts
12 pins
Flags
firmware-updatableweather-sealedrequires 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

Functionally similar to Viltrox EF-EOS R5; Viltrox tracks slightly better on EF L super-telephotos in side-by-side tests, Commlite costs slightly less. Both lack the weather sealing of Canon's official adapter.

Firmware history

Firmware history

  1. v1.0
    • Initial release — Canon EF / EF-S onto Canon RF (R / RP / R5 / R6) with AF / IS / electronic aperture
  2. v2.0
    • R5 II / R6 II / R7 / R10 / R8 PDAF rule alignment
    • EF-S APS-C crop-mode handling refinements

Approximate milestones — verify against the Commlite firmware page for the authoritative changelog.

Common questions

Should I get the Commlite CM-EF-EOS R over Canon's first-party EF-EOS R?
If budget matters and you don't need weather sealing, yes — the Commlite is ~50% cheaper with similar AF / IS / electronic aperture preservation on every EF / EF-S USM / STM lens. Canon's official adapter is weather-sealed and ships in three variants (plain, Control Ring, Drop-In Filter); the Commlite only ships a plain variant and isn't weather-sealed. For heavy professional use with weather-sealed RF body + EF L super-telephoto, the Canon is worth the premium. For everyday RF use, Commlite or Viltrox EF-EOS R5 saves ~$80-100.
Does it preserve EF-S lens APS-C crop mode on RF bodies?
Yes — v2.0 firmware refined EF-S crop-mode handling. Mounting an EF-S lens on a full-frame RF body (R5 / R6 / R3 / R5 II / R6 II / R8) auto-engages 1.6× APS-C crop mode just as the first-party adapter does. On crop RF bodies (R7 / R10 / R50 / R100) the body is already in APS-C natively, so no crop-mode switching is needed.
Will it autofocus on the R5 II or R6 II?
Yes — v2.0 firmware (2022) added R5 II / R6 II / R7 / R10 / R8 PDAF rule alignment. AF tracking is slightly slower than the same EF lens on Canon's first-party EF-EOS R, but Single-Servo and Continuous-Servo both work reliably on USM / STM EF lenses. EF L II / III primes (24 / 35 / 50 / 85 / 135) all preserve AF, IS, and electronic aperture.

Head-to-head comparisons

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