Canon EF Extender 1.4X III Teleconverter
The Canon 1.4X III is a lens accessory from Canon — known for its 1.4x Focal Length Extension and 1-Stop Light Reduction. Check GearFocus for current availability, with buyer protection on every purchase.
Canon EF Extender 1.4X III Teleconverter
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Overview — Canon 1.4X III
Key Features — Canon 1.4X III
1.4x Focal Length Extension: Multiplies the focal length of compatible Canon EF lenses by 1.4x, effectively turning a 300mm lens into a 420mm for increased reach.
1-Stop Light Reduction: Reduces maximum aperture by one stop, so a lens with f/2.8 becomes f/4 when the extender is attached.
Autofocus Compatible: Retains autofocus functionality with compatible Canon EF telephoto lenses, allowing uninterrupted AF operation in the field.
Canon EF Mount: Passes full electronic communication between camera body and lens, preserving EXIF data, metering, and AF systems natively.
Third-Generation Optics: The Mark III version features an updated optical formula with improved coatings to reduce chromatic aberration and maintain image quality compared to earlier versions.
Full-Frame Coverage: Designed for Canon's full-frame EF ecosystem, making it compatible with both full-frame and APS-C Canon DSLR bodies.
Specifications — Canon 1.4X III
| Spec | Detail |
|---|---|
| Lens Format | Full Frame |
| Camera System | DSLR |
| Zoom Prime | Prime |
| Auto Focus | Yes |
| Focus Type | Auto, Manual |
| Focal Length Range | Telephoto |
| Image Stabilization | None |
| Weight unit | g |
| Weight value | 225 |
| Mount lens | Canon EF |
| Compatible Mount | Canon EF |
Description — Canon 1.4X III
The Canon EF Extender 1.4X III Teleconverter is built around the Canon EF lens mount and is designed specifically for DSLR cameras operating within the Canon EF system. It supports a full-frame lens format, making it compatible with Canon's full-frame EF lens lineup. One of its key practical strengths is autofocus support, with both auto and manual focus modes available depending on the attached lens and shooting preference.
The extender falls into the telephoto focal length range category and is classified as a prime configuration — it is a fixed-magnification device rather than a variable one. At 225g, it adds a manageable amount of weight to a shooting kit. Image stabilization is listed as None on the extender itself, so photographers relying on optical stabilization will need to ensure their attached lens provides it.
No filter thread size is listed in the specifications. Overall, this accessory is a Canon-native EF system solution for DSLR shooters looking to extend their telephoto reach while retaining autofocus capability.
Pros — Canon 1.4X III
- ✓Supports autofocus operation within the Canon EF system
- ✓Compatible with full-frame Canon EF lenses, offering broad system compatibility
- ✓Designed for Canon DSLR cameras, ensuring native mount integration
Cons — Canon 1.4X III
- ✗No image stabilization provided by the extender itself
- ✗Compatible only with Canon EF mount lenses — no EF-S, RF, or third-party mount support listed in specs
- ✗Filter thread size is not specified, limiting accessory planning information
Videos — Canon 1.4X III
Canon EF 1.4x III Extender Review | Using Canon 7D II & Canon 100-400mm f/4.5-5.6 II — Espen Helland
Frequently Asked Questions — Canon 1.4X III
What camera mount does this extender use?+
The extender uses the Canon EF lens mount. It is designed for use with Canon EF system lenses on DSLR cameras, as indicated in the specifications.
Does this extender support autofocus?+
Yes, the specifications confirm that autofocus is supported. Both auto and manual focus modes are listed as available focus types.
Is this extender compatible with full-frame cameras?+
The specifications list the lens format as Full Frame and the camera system as DSLR. It is designed for use within the Canon EF full-frame system.
How much does this extender weigh?+
The extender weighs 225g according to the specifications. This is worth factoring in when calculating the total weight of your lens-and-body setup.
Does this extender have image stabilization?+
No. The specifications explicitly list image stabilization as None for this extender. Any stabilization in your setup would come from the attached lens itself, if it offers that feature.
Is there a filter thread on this extender?+
The filter thread size is not specified in the product data, so this cannot be confirmed. You should check directly with Canon or the seller for filter attachment options.