Canon - Extender EF 1.4x III Extender Lens - White

Canon EF 1.4x III Extender (Teleconverter): Enhance your existing camera lens with the improved autofocus performance and increased distance clarity of this 1.4x III extender.

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Best Buy Customer Reviews

tack sharp5 Posted by: from: on I've only used this in connection with a 100-400mm ver 2 Canon lens, but in this combination, the extender yields images that are very sharp as compared to this lens without the teleconverter. Excellent product

0 out of 0 found this review helpful.

Works Great5 Posted by: from: on I own a Canon EOS 7D Mark II with a crop factor of 1.6 and mounted with an EF 100-400mm F/4.5-5.6L IS II USM. This gives me a lens of 160-640mm, and with the EF 1.4 III extender mounted between that it gives me a lens of 224-896mm. Which is perfect for shooting airshows, and any distance shots. (((( I originally bought an EF 2x III extender for this setup (and it gave me a lens of 320-1,280mm ) but it would NOT let me use the Auto Focus system (because it was above F/8 but I did not know this at the time), but I could still use the 2X in the manual mode with NO problems. )))) So I called Canon and they said that I needed the EF 1.4 III extender with this setup if I wanted to use the AF system of the 7D, because this would keep the F/ number below F/8. And Canon also said that the 2x III extender was better suited for any F/2.8 lens, because it would keep the F/ number below F/8.

1 out of 1 found this review helpful.

AF worksgreat with Canon 100-400L lens & 7d MII5 Posted by: from: on Extender 1.4 works better than I expected with my Canon 100-400 L lens and Canon 7d MII. Going to try the 2.0 extender next.

3 out of 3 found this review helpful.

didnt work with 5 d mark iii camera1 Posted by: from: Harrisburg on This would not automatically focus with canon 5dmiii using a canon 100-400 lens even when camera softwaer was,done. item was returned.

1 out of 5 found this review helpful.

Great Extender5 Posted by: from: on Used this extender to add a little more range for our 400 lens, easy to use and adds about 40% more distance

0 out of 0 found this review helpful.

Does what it is made for.4 Posted by: from: Bradenton, FL on So far I am very happy with the product. I have not noticed much difference between the AF or IQ with or with out on the 70-200

1 out of 1 found this review helpful.

What a great addition to my collection5 Posted by: from: on After renting 1.4x for a while, I decided to buy one. So glad to have it in my camera pack. Canon hands down makes the best glass and this extenders are a must have for any wild life photographer. I would highly recommend the CanonEF 1.4x III Extender it's so smooth and tack sharp.

2 out of 2 found this review helpful.

Great quality lens4 Posted by: from: Round Rock, Texas on Tried the 2x and found the the 1.4 to work best. Highly recommend it.

3 out of 3 found this review helpful.


1 out of 8 found this review helpful.

not for efs 100-400 L5 Posted by: from: Houston on Compatability chart says it works with EFS 100-400 mm L lens-It DOES NOT work in auto focus AF mode.. Canon support verified does not AF. Returned item. Arrived on time in good condition. Easy to understand instructions.

10 out of 16 found this review helpful.

    What's Included

    • Canon Extender EF 1.4x III Extender Lens
    • Owner's manual

    Ratings & Reviews

    Overall Customer Rating:
    90% of customers would recommend this product to a friend (9 out of 10)

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    Product Features

    Compatible with select EF Canon lenses

    Use with your existing fixed focal length L-series lenses and EF-mount camera for optimum aperture size, autofocus speed and durability.

    Maximize existing lens capability

    Increase your focal length by up to 40% with a 1.4x zoom for improved clarity and focus over greater distances. Also reduces aperture size by 1 stop.

    Faster capture speeds with built-in microcomputer

    Functions seamlessly across camera body, lens and extender enabling swift lens response times and sharp picture quality, even when photographing moving subjects.

    Resists scratches and damage

    Fluorine coating repels finger prints and light dust and makes the lens easier to clean.

    Accessories included

    Comes with lens cap, rear lens dust cap and case.


    Will not autofocus unless existing lens has aperture of f/5.6 or greater.

    Product images, including color, may differ from actual product appearance.