Canon EF 1.4X III Telephoto Extender for Canon Super Telephoto Lenses

As an amateur photographer who lives in Alaska and loves to shoot wildlife I was wanting this badly and finally grabbed it right before I went on a bear viewing trip. Design: As with everything with Canon, these are really well designed and work perfectly. They even updated the color on these to help them match better with the newer version of the 70-200 and the 100-400, so that is a nice bonus. It is light but still has some good weight to it so you can feel the quality construction. As for the use of this, it works perfectly with the EF lens series. I can also verify that it works with the RF-EF adapter on the mirrorless cameras. REMEMBER THAT THIS WILL MOVE EVERYTHING UP ONE STOP ON THE CAMERA and EFFECTS THE AUTOFOCUS POINTS. MICRO-ADJUST THE CAMERA TO ENSURE BEST FOCUS or, like me, your photos will just seem to be slightly soft on focus Cost: I purchased it for $340, currently $429 Overall: I am a Canon equipment user and this is just another in a long line of great products Positives: ++Cost (but I got it almost 25% off) ++Design Negatives: --Autofocus effects --F-Stop adjustment Would I recommend: Absolutely/Borderline. Absolutely I would buy it again, borderline if you are not sure what to do with the other settings on your camera. Photos attached with the adapter on

Quick and easy to use in the field. I use a crop sensor camera. This extender is just enough & helps me not have to shell out huge bucks for a 800mm lens, and does the trick. Must stop down 1-2, and photo is a tad grainier; however, I need to micro-adjust my camera first before totally blaming the softness of my shots on this extender. Works well, and glad I have it. Easier than carrying around my Tamron 600mm weight wise, although it does add a bit of forward weight. For the $, I'd say it's a good choice for me. I have the 2x extender, but find this extender's pic quality is better, and less cumbersome to shoot with.

With the Canon EF 1.4X III you can extend your lens focal length and still have fantastic picture quality for much less than buying a new lens. NOTE: The auto focus compatibility is a little confusing. Canon states that auto focus will work if your lens max lens aperture is 5.6 or faster. I also verified that Canon states that this extender is compatible with the Canon EF 100-400 f/4.5-5.6 lens. So, I assumed that the auto focus would work with my Canon EF 100-400 L IS lens since it is a f/4.5-5.6. But, the compatible aperture opening is figure for "after" your EF 1.4X III has been attached to your lens. Thus, the decreased aperture opening put the lens out of auto focus ability. I thought this was very misleading. The auto focus works well with this on my EF 70-200 f/2.8 lens, but I already have a EF 2X II that works fine with that. I highly recommend this Canon EF 1.4X III Extender, but be aware of autofocus compatibility.

I considered giving the Canon EF 1.4X III Telephoto Extender five stars, and when all is said and done, it may/probably does deserve it. The first time I used the extender (with my Canon 70-200mm telephoto zoon lens), it was to photograph birds, including hummingbirds, at/near my feeders. In that instance, some of the resulting photos turned out slightly fuzzy, and my first thought--and the reason for four-star instead of five-star rating--was that it wasn't as good as advertised. However, I now believe that the reason for the fuzziness was that I was a little too close to what I was photographing; that I'm not completely sure is the reason I gave the lens four stars instead of five. Since that first experience, I have used the 1.4x extender to take more bird photos as well as photos at youth baseball games. In those instances, the photos turned out beautifully. I'm an amateur, but I felt/feel the auto-focus is fast, and the photos appear clear. I have a pretty good camera and zoom lens, which definitely help, but a poor extender would negate those attributes. Instead, the Canon EF 1.4X III extender, working with my camera and lens, produced sharp photos, even when I used the continuous shooting mode and even after I cropped photos because the main subject was fairly distant. All in all, to this point...I have been using the extender for about a month...I am very happy with the results.

This review is based on use with a Canon EOS 5D mark IV and the Canon EF 100-400mm f/4.5-5.6 L IS USM II lens. The Canon EF 1.4X III Telephoto Extender gives this lens a max of 560mm f/8, so you loose one full stop. To put that in perspective, from f/5.6 to f/8 (one full stop), you are only getting 1/2 of the light that you were getting at f/5.6. For me, there was a slight learning curve and it took some fiddling with settings to get good exposure in lower lighting. The day I got this, it was one of those overcast days where the sun just looks like a smudge in the sky, but I just didn't want to wait for better conditions, and really, why should I? It was a pretty good test actually. Five of the shots I've attached were taken that day; the Downy Woodpecker (shot 2), two of the Eastern Bluebirds (shots 3 & 4), the Dove (shot 5), and the Tufted Titmouse (shot 6). My settings ranged from 1/200th shutter / ISO 1200 to 1/1000th shutter / ISO 800, and the darker images were at f/8. Most were taken under 60 feet away with the flying birds being over 150 feet +/-. All shots have been cropped to various degrees, but generally, I crop about 50% of the pixels away. There is a wee bit of IQ loss, but nothing that you will notice on prints from 11x17"ish below and for general use, like Facebook, forums, and other places you might want to post images, even high quality. Once you convert to JPeG or other "lossy" formats, it's a moot point anyway. I am a "pixel peeper" so I did notice some IQ loss when zoomed past 100%, but honestly, how many people do that?. I don't see any color fringing or vignetting , even though that has been reported, however, I seem to concentrate on the subject, which I know will be cropped, so if it is indeed there, it's of no concern to me. I tested it, using the mentioned 100-400mm lens, on the 5D mark IV, the 7D mark II (See revision), and the Rebel T7i. All focus points worked on the 5D mark IV and Rebel T7i, but only the two center focus points worked on the 7D mark II. I tested in outside lighting that wasn't optimal. I was really surprised because reviewers have stated that you loose some peripheral focus points. Focus did slow down in low light on all the cameras I tested, but honestly, it wasn't that bad. Good lighting was a different story, all cameras AF was snappy as usual. Now, when Canon says the Canon EF 1.4X III Telephoto Extender will only work with certain lenses, it has nothing to do with optics or light, it just plain wont fit other lenses. For the heck of it, I tried to attach it to an EF 70-300mm f/4-5.6 L IS USM II, an EF 70-300mm f/4-5.6 IS USM II (non L), and an EF 100mm f/2.8 (I know, I just wanted to see), and it just would not fit the lens. The front element of the Canon EF 1.4X III Telephoto Extender went too far into the lens to allow it to attach. This device will not replace a dedicated long lens, but it will sure improve your reach with very little loss in IQ. You just have to pick your lighting battles. **EDIT August 28, 2019** My initial review stated that the EOS 7D mark II retained all focus points and though I can't explain how I missed that, you DO loose all but the CENTER TWO focus points with the 7D2, EF 100-400mm L II and this extender, i.e., the center focus point and the smaller one inside of it. You can toggle between these two, but no others are available. I suspect it's a sensor and firmware issue because the cheaper Rebel T7i has no problem dropping focus points with this combo. I sincerely apologize if I've misled owners of the EOS 7D mark II.

Flawless! Be aware you will lose one f-stop, though.

I have been a Nikon user for a long time with my last camera being D810. I was about to upgrade to D850, but instead decided to buy the Sony A7R iii due to its form factor and its ability to use lenses with different mounts via adapters. Since then, I have purchased Sony FE 12-24mm f/4, FE 24-105mm f/4 and a large number of Canon EF mount lenses coupled with the Sigma MC11 adapter. I will post my experiences with other lenses elsewhere. This review focuses on the use of Canon extenders with EF 100-400mm II L lens in my system. Please be advised that all my conclusions are valid only for my system. The results may be different for other camera/lens combinations. I purchased all three versions of Canon 1.4x extenders (used) to perform a side by side comparison using brick wall images. Since, it is mostly pointless to use extenders at smaller focal lengths, I did the comparison only at 400mm for an effective focal length of 560mm. Below are my findings. 1. All three extenders had no problem with auto-focus in my system without any obvious difference. However, my primary objective was to compare image quality. I did not perform any test for auto-focus under difficult conditions. 2. At all apertures (f/8, f/11 & f/16), 1.4x ii was only marginally better than 1.4x at one of the extreme corners. There will not be any difference in real world images. If you are thinking of buying a used one, I wouldn't recommend paying significantly more for ver ii. 3. I also performed one interesting test to investigate the utility of even having an extender in the first place with a super sharp lens like 100-400mm ii l. I cropped an original image by the 1.4x factor with Photoshop and then upsampled the cropped image to the original 42MP image. I was shocked to see that the upsampled image was virtually indistinguishable from the images with the extender. Sure, in extreme corners you may find some tiny differences in detail (if you look really hard!). But keep in mind that with the extender, you are adding size/weight, losing one stop of light apart from the inconvenience of putting it on and off as needed. For me, I wouldn't bother to use ver. i or ii in my system. 4. With ver. iii, I could easily see the added sharpness at extreme corners compared to the earlier versions. The center looks pretty similar for all 3 versions. Needless to mention that the upsampled image was inferior this time. Again, the difference is not huge but noticeable. If you need the extra reach, my recommendation will be to buy it (if you can afford it). 5. I plan to do a comparison with Kenko Teleplus Pro 1.4x DGX. I will update the review once the comparison is done. 6. I am not posting any images since the comparison is only meaningful at full resolution.

I just assumed this would fit my Canon lens. It did not. There was no possible way to attach it. After reading the list of compatible cameras that was in the enclosed users manual/directions sheet, I saw that my lens was probably the only Canon lens this will not work with. The product looked very nice and felt sturdy and well made. Just don't buy one without looking at the compatibility list, which is on the Amazon information page, if you look for and click on the link to the user manual. Had I noticed it, I would not have ordered.