EF to RF Adapter

Canon Mount Adapter EF-EOS R 0.71x

An EF to RF adapter to use the broad range of Canon EF lenses on the EOS C70 camera.


  • Magnification


  • Compact

    77.2 x 76.6 x 20.7mm Approx.

  • Lightweight


New firmware is available from December 3rd, 2021, offering additional lens support via the 0.71x Mount Adapter, and more. For more information and to download now, please follow the link.


Adapt EF lenses for use on RF Super 35mm System

The MOUNT ADAPTER EF-EOS R 0.71x is an EF to RF mount adapter for using the wide range of full frame Canon EF lenses on the EOS C70.
EF Lens on RF mount, EF to RF MOUNT ADAPTER R 0.71x


Maintain full frame angle of view

The adapter gives the same angle of view when utilising full frame lenses on the Super 35mm sensor of the EOS C70, by adapting the focal length by a factor of 0.71x from full frame format to Super 35mm format.
Person holding  EOS C70 with RF lense,  Full frame format, Super 35 mm format


One stop brighter

By reducing the focal length of the lens, MOUNT ADAPTER EF-EOS R 0.71x increases light transmission, effectively increasing the f/stop value of a lens. For example, an F2.8 lens becomes approximately F2.0, for low-light shooting and lower signal noise.
EF to RF MOUNT ADAPTER R 0.71x, Increased light transmission


Superior communication between lens and body

Full communication between EF lenses and the camera body is maintained, with support for Dual Pixel CMOS AF1, as well as peripheral illumination and chromatic aberration correction. The adapter also transmits information from the lens, and is displayed on screen (F value, focal length and lens metadata are supported).
EF to RF MOUNT ADAPTER R 0.71x,  Superior commutation between lens and body, Dual pixel CMOS AF, Chromatic aberration correction, peripheral illumination

No compromise construction

Designed for reliability and durability, the included locking plates secure the adaptor to the body with four screws. Shoot with confidence even when using large and heavy lenses.

EF to RF MOUNT ADAPTER R 0.71x, durability, locking plates


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EOS C70 whats in the box

What's in the box


  • 2 x Locking Support Plates & 4 x Screws

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  • Canon Mount Adapter EF-EOS R 0.71x
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    1. All data is based on Canon standard testing methods except where indicated. Subject to change without notice.
    2. A combination of specific lens models and lens settings may cause vignetting to appear on the edges of the image when using the EF-EOS R 0.71x mount adapter