Viltrox EF-R3 Pro – EF to RF Cine Focal Reducer for RED KOMODO / Canon C70

Viltrox EF-R3 Pro – EF to RF Cine Focal Reducer for RED KOMODO / Canon C70

Viltrox has released the Viltrox EF-R3 Pro 0.71x focal reducer for the Canon C70 and the RED KOMODO. Optically, this is the exact same adapter as their EF-R3 EF to RF focal reducer, however, this model features a more professional locking EF mount. Let’s look at how this can benefit your shoots.

Best known as a budget photo supply company, Viltrox produces lenses, adapters, lights, monitors and cages.  Their products are generally well-built, and cost considerably less than their competition. And, the EF-R3 Pro is no exception.

This 0.71x Lens Mount Adapter allows a full-frame Canon EF-mount lens to be mounted onto an RF mount camera with an S35/APS-C sensor.  The adapter’s optics help to maximize the lens’ apparent angle of view while providing a one-stop increase for the camera over the lens’ aperture range.

When paired with a compatible autofocus lens, as well as camera-controlled aperture functions, this adapter is intended to allow those features to be used. If an attached lens is capable of generating Exif metadata, when used with a directly compatible camera, the adapter saves that information along with image files generated with a combination of the lens, a compatible RF Mount Cine Camera, and the adapter.

To learn more about focal reducers, check out our previous post Focal Reducers – Lens Adapters That Change the Game.

Viltrox EF-R3 Pro Locking Mount

The locking mount provides a tight, rock-solid contact between the lens and the Viltrox EF-R3 Pro. That sturdy connection ensures that the lens will not shift inside the mount while using a heavy cine lens and a follow focus motor.

For the C70, Viltrox includes a fixed plate that attaches the EF-R3 Pro more securely to the camera body. However, no additional mounting points are provided for other cameras or rigging situations.

When in use with the RED KOMODO, a camera cage with an additional lens adapter support is necessary to fix the adapter to the camera’s body. Bright Tangerine and Vocas both make cages for the RED KOMODO with adapter support accessories.

Lens Compatibility

Not every full frame lens is compatible with the EF-R3 Pro. Viltrox provides a list of compatible lenses on their website. The EF-R3 Pro has a micro USB port for future firmware updates.


Both Canon and Metabones offer EF to RF focal reducers that are compatible with the Canon C70 and the RED KOMODO. Both have minor advantages and disadvantages compared to the Viltrox EF-R3 Pro, but Viltrox lists their adapter for nearly half the price, in comparison.

Metabones’ Cine Speed Booster, however, is the only other focal reducer to date that features a locking EF mount. In fact, there aren’t many regular EF to RF adapters with a locking mount on the market and they’re all priced at roughly twice as much as the Viltrox EF-R3 Pro.

So, if you’re in need of a locking EF mount for your KOMODO or C70, this should definitely be something you’re considering.

Pricing and Availability

The Viltrox EF-R3 Pro lists for $316 and is currently available and in-stock at all resellers, and on Viltrox’ website.

The Canon Mount Adapter EF-EOS R retails for $599.99, and the Metabones Cine Speed Boosters sells for $529. KipperTie’s Adapta RF/EF, which sells for about $725, is the only other adapter to offer a locking EF mount. The Adapta is just a lens adapter, not a focal reducer.

The Viltrox EF-R3 Pro clearly offers a lot of value for its price.

Have you used Viltrox focal reducers on your cameras? How do they stack up against the competition? Let us know in the comments below.

1 Comment

Notify of

Sort by:
Sort by:

Take part in the CineD community experience