Customer Ratings & Reviews

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.

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.

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.

The Canon 1.4x teleconverter can help create excellent photos. Slight loss of maximum f/stop but also can obtain greater DOF (depth of field) at smallest f.stop. Keep lens surfaces clean or dust spot in photos.

Creates great versatility for my existing lenses. The quality of the image and the usability is terrific.

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.

Used this extender to add a little more range for our 400 lens, easy to use and adds about 40% more distance

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

This is the best extender for the money. It does exactly what it says, enhancing picture quality.

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

The main reason I bought this extender is to take pictures of moon coupled with my Canon EF 400mm 5.6L lens. Pictures turned out to be great.

i been using this for over a month since i got this and shooting birds flying ,, very happy with sharp details even with subjects over 500 feet away

Tried the 2x and found the the 1.4 to work best. Highly recommend it.

Works well with my Cannon Mark ll and my 100-400. EXCELLENT!!

The extender is used in conjunction Canon 7D Mark II and 100-400 mm lens. It is used for outdoor/birding photography. The extender makes many otherwise hard to photograph images available.

Great accessory for the Canon 70-200 f2.8L IS II lens or any of the Canon L series white telephoto and zoom lens.

This would not automatically focus with canon 5dmiii using a canon 100-400 lens even when camera softwaer was,done. item was returned.

I BOUGHT IT FOR MY SON FOR HIS BIRTHDAY AND HE LOVES IT!!!!! HE SENDS ME PHOTOS ON MY IPHONE AND I LOVE THEM!!

Excellent Canon accessory for their zoom, and telephoto, lenses. At f/2.8 little loss of fast aperture and f/22 increases to f/44 for greater depth of field. EXIF data says it makes 70-200mm equivalent to 422mm in 35mm-format (APS-C D-SLR).