Canon 1.4X EF Extender III Teleconverter (L Series Tele/Zoom Lenses)

Canon's 1.4x EF Extender III adds reach without sacrificing AF.

The Extender EF 1.4x III multiplies focal length by 1.4x across compatible Canon L-series super telephoto and zoom lenses, giving wildlife and sports shooters meaningful extra reach before cropping ever enters the conversation. The 7-element, 3-group optical design is built specifically to keep chromatic aberration in check at telephoto distances, where fringing on high-contrast edges is a persistent problem with lesser glass. Careful element placement and dedicated coatings address ghosting and flare, which matters when you're shooting into bright skies or toward stadium lights.

The built-in microcomputer maintains full communication between body, lens, and extender, so autofocus, image stabilization, and EXIF data all behave as expected than degrading or dropping out. At 7.9 oz and just 1.1 inches long, it adds almost nothing to a kit bag. Fluorine coating on external glass surfaces keeps fingerprints and smears off the optics without requiring constant cleaning in the field. Dust and water resistance matches what Canon L-series glass demands from any accessory in its system.

Who It's For

Wildlife photographers working at distance will find the 1.4x multiplication extends a 500mm lens to 700mm while keeping autofocus fully operational through the microcomputer link. Sports and press shooters gain reach at events where physical proximity is limited, without adding significant weight to a long-lens setup. Birders using Canon's super telephoto primes get a direct upgrade path from their existing glass than a second lens. Travel photographers who carry a single telephoto zoom can squeeze more working distance from one lens on safari or at air shows.

Key Features

• 7-element, 3-group optical design minimizes chromatic aberration
• Built-in microcomputer maintains AF, IS, and EXIF communication
• Fluorine coating resists soiling, smears, and fingerprints
• Careful lens placement reduces ghosting and flare at telephoto distances
• Canon EF mount for L-series super telephoto and zoom lenses
• Dust and water resistant construction matches L-series standards
• 7.9 oz and 1.1 inch length adds minimal weight and bulk

FAQ

Will autofocus still work with the 1.4x extender on my telephoto lens?

Yes. The built-in microcomputer maintains full communication between body, lens, and extender, so AF, IS, and EXIF data all function normally rather than degrading or dropping out.

How much does this add to the weight and length of my setup?

At 7.9 oz and 1.1 inches long, it adds almost nothing to a kit bag or shoulder rig.

What's the difference between this and cheaper third-party extenders?

The 7-element optical design is built specifically to minimize chromatic aberration at telephoto distances, where fringing on high-contrast edges is a real problem. Careful element placement and dedicated coatings also address ghosting and flare when shooting into bright skies or stadium lights.

Does the fluorine coating need special care?

No. It keeps fingerprints and smears off the optics without requiring constant cleaning in the field, and it's the same dust and water resistance you get from Canon L-series glass.

Which Canon lenses is this compatible with?

It's designed for Canon EF L-series super telephoto and zoom lenses. Check your lens manual to confirm compatibility, as some older or specialty lenses may have limitations.

How much reach does 1.4x actually add?

A 400mm lens becomes 560mm. A 600mm becomes 840mm. You get that extra reach before cropping ever enters the conversation.

Will I lose shutter speed when I attach this extender?

Yes, you'll lose approximately one stop of light transmission. A lens with a maximum aperture of f/2.8 will effectively become f/4 with the 1.4x extender attached.