Quick Summary
The VILTROX EF R3 0.71x Speed Booster is an auto focus mount adapter for Canon EF lenses to RF mount cameras including EOS C70, RED Komodo, R5, and R6. It is designed to convert light transmission from full frame Canon EF lens to the Super 35mm image format, extend the angle of view, and increase maximum aperture by 1 stop.
Who It Is Best For
This adapter suits filmmakers and photographers who want to use Canon EF lenses on compatible RF mount bodies and keep practical lens functions where supported. It is a sensible choice if you want a wider view, more light in lower light settings, and a mounted setup that can also support tripod or quick release use through the foot.
What To Know Before You Buy
The adapter is intended for compatible lenses and cameras, so check your exact lens and body combination before ordering. Autofocus, camera controlled aperture functions, and Exif metadata support depend on the lens being used.
Pros: It offers a 0.71x speed booster effect, includes a detachable tripod foot with a 1/4 inch 20 accessory thread, and has a micro USB port for firmware updates.
Cons: Some useful functions depend on lens compatibility, so not every lens will behave the same way.
Common Buyer Questions
What does a 0.71x speed booster do?
It is designed to extend the angle of view, improve optical sensitivity, and reduce the crop factor.
Will autofocus work with every lens?
No. Autofocus is intended for compatible lenses that already include autofocus support.
Can it pass on aperture control?
Yes, if the attached lens supports camera controlled aperture functions.
Does it support Exif metadata?
It is designed to allow Exif information to be saved when the attached lens can generate that metadata.
Can I mount it on a tripod?
Yes. The detachable tripod foot has a 1/4 inch 20 accessory thread for direct attachment to compatible supports.
Key Details
| Detail | What it means in use |
|---|---|
| Model | EF R3 |
| Type | 0.71x speed booster auto focus mount adapter |
| Lens mount use | Canon EF lens to RF mount |
| Compatible cameras named | EOS C70, RED Komodo, R5, R6 |
| Optical effect | Extends angle of view and optical sensitivity |
| Aperture effect | Increases maximum aperture by 1 stop |
| Optical design | 4 elements in 4 groups |
| Tripod foot | Detachable foot with 1/4 inch 20 accessory thread |
| Firmware update port | Micro USB port |
Final Buying View
If you want a Canon EF to RF mount adapter with a 0.71x speed booster design, the VILTROX EF R3 offers a focused set of features for compatible camera and lens combinations. It is built for users who want the benefits of a wider view, stronger light transmission, and support for selected lens functions where available. Check your lens and body pairing before ordering, then choose it if those features match the way you work.
