Testing Eye AF on the Sony a7R III With Adapted Canon Glass

One of the coolest parts about Sony cameras is the ability to adapt a metric ton of glass to them, but in the past, that has generally meant taking a gamble on autofocus performance. Nonetheless, the a9 and a7R III have both made major steps in this area, and this video shows just how good things have gotten.

Coming to you The Brotographer, this video shows some practical tests for shooting with Eye AF when using the Metabones adapter and a variety of Canon and third-party EF mount lenses. So far, it appears the results are mostly good news, with a few small quirks, but some definite improvement and very usable performance for most applications. A small note, though the video says it's not possible to use Eye AF on the a7R II with adapted lenses, it is possible in advanced mode, but that reverts to the much slower CDAF and isn't particularly useful, whereas the PDAF shown in the video is snappy. It's actually interesting, as lenses that are notoriously difficult to focus on a DSLR (such as the Canon 85mm f/1.2L II) really benefit from the on-sensor autofocus of the a7R III, and with the improvements in speed, they seem to end up performing better overall on the Sony than on their native mount. 

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Alex Cooke is a Cleveland-based portrait, events, and landscape photographer. He holds an M.S. in Applied Mathematics and a doctorate in Music Composition. He is also an avid equestrian.

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Thanks for posting this, Alex. I’ve been searching for exactly this review for a few days and couldn’t find what I was looking for until this popped up on Fstoppers. I’ve given up on Canon bodies, but, like many, I have a bunch of great glass. Not going to waste years of my life waiting to see if Canon makes a D850/a7RIII equivalent in 2021 while the rest of the industry is innovating like crazy. Now I know I can use Sony bodies going forward. This video was exactly what I needed. So glad to no longer have to deal with Canon’s idiotic product segmentation. Sony (and Fuji) actually want my money, so I’m happy to buy from them.

Be interesting to see how Canon behaves going forward with regard to keeping up with the industry now that they no longer can hold people hostage with their glass. I’ll be on a Sony body by then, so “interesting” is all it will be for me. It won’t matter in terms of my purchasing.

That's the exact boat I'm in. I bought an a7R II to dip my toes in the water, but held on to my 5D IV because the AF wasn't quite there yet, but I think I'm going to sell both and grab an a7R III now.

This question is for both of you.
Do you feel that the Sony/Metabones combination is a solid solution for heavy pro use?
I currently use Canon with splendid glass as Lenzy points out however my 5DsR is falling short in a few ways and I am looking for a solution that can reliably deliver in a demanding pro environment.
I shoot architecture and can have as many as three large projects in a week. Tomorrow I begin a 4 day shoot and will be using my Canon bodies but was wondering if I could do this with the Sony/ Metaboes combination. Thanks.

Hey Mark, I've owned Canon bodies for a long time and still do. I bought a Sony A7R2 well over a year ago to use as my main camera body. I'm currently using the Sony A7R2 professionally with a Metabones Adapter and my Canon glass. It performs really well. Would I shoot sports with it? No. I'd buy Sony glass if I were doing that. I'm a commercial photographer and I shoot a variety of subjects, but I specialize in product and architectural imagery. For those, I have no complaints with the autofocus system using adapted Canon glass. Even for portraits it works really well.

There are times in low light were I noticed slower autofocus, but for the most part, I've been pretty happy with adapting my Canon Glass. If you want autofocus during video, it can work. But it's not as good as Canon's Dual Pixel technology. That said, Sony glass would be the better way to go if you need autofocus during video. But I have found that my Sony A7R2 shoots much better video quality than my Canons, even with Canon glass. Plus I can use my Canon crop sensor STM lenses for video on the Sony as well. That's a huge advantage over the current Canon offering.

Buttom line, the Sony A7R2 rocks, even with the Metabones Adapter and Canon lenses. I'd love to eventually buy some Sony Glass. But it's nice to know that I can bounce between Sony and Canon if I need to. But yeah, as far as pro use goes, dude I use Canon glass on my Sony and I've been more than happy with it. There are some caviets of the Sony A7R2, which the A7R3 have seemed to address. I wrote an article a while back about how to wirelessly trigger the Sony A7R2 while shooting tethered which was a big one for me: https://fstoppers.com/originals/how-wirelessly-trigger-sony-a7r-ii-while...


Hi Brian. What settings are you using on your a7R II to shoot video with Canon glass? I picked up a a7R III and the focus seems to never lock on (shooting environment/objects and not human subjects). What are your autofocus settings set to on yours? Thanks!

Hi Jimmy,

The adapted Canon lenses are have way more reliability when shooting stills than they do in video. Most of the time when I shoot video with the A7R2 though, I'm using manual focus. Using the Canon glass on the Sony, I've never relied on autofocus during video for any client shoot. That said, I have experimented with autofocus using a metabones adapter version lV and some Canon glass. It doesn't work nearly as well as my Canon 70D dual pixel autofocus system. But it does in fact work....just not reliably.

Here's what I've found. I own various Canon full frame lenses and crop sensor lenses. If you have any Canon crop sensor lenses that are labeled STM, they tend to yield much better results during video auto focus. First off, you have to enable the advanced mode on the metabones adapter, by turning on your camera, pressing the metabones adapter button, then putting the lens on. This enables the advanced mode. Then go to the video mode on your camera, make sure the autofocus is set to "AF-C" (continuous auto-focus) and set your focus area to "wide." By doing these things, in good light, adapted canon lenses can do a decent job of autofocus during video.

I don't currently own any Sony glass, and I know their autofocus during video is really good, I just personally haven't used any. Coming from a Canon background, I really miss my dual pixel autofocus system. I still have my Canon 70D around for that specific reason.

Here's a quick sample video that I posted to my instagram page back in June using continuous autofocus on the A7R2 using a metabones adapter and a Canon 24mm STM: https://www.instagram.com/p/BVK_R9egr1a/?taken-by=digitalartthatrocks

One last note, if you're using Canon crop sensor glass, you'll also want to go into your camera settings and turn on "Super 35" which is crop sensor mode. This will also give you better 4K video on the Sony.


Hi Brian. Thanks for the informative response. I don't own any STM or APS-C lens, and, as you said, I'm noticing slightly better focusing when set to Wide. I don't usually shoot a lot of video, but wanted to know how to set it up in case I have a need for it. I am also considering picking a native Sony glass in the future if I ever want to shoot video and take full advantage of the camera/system's AF.

Thanks again for the info!

Glad to help, I shoot a decent amount of video and the Sony delivers amazing quality. Most of the time when I shoot video, I set the camera to manual focus anyway, but there are times when I'd like to track moving subjects. For that, I rely on my Canon since I don't have any native Sony glass. Just remember you can make awesome videos with the Sony and Canon glass and the focus peaking technology in the camera makes it much easier to use manual focus. Cheers!

Absolutely, especially if you're doing architecture. There's no reason the adapted autofocus couldn't keep up with that, plus the Sony has great MF aids.

I'd say 75% of the time for the kind of work that I do, I'm using manual focus. And having the focus peaking technology in the Sony is a nice benefit to using their cameras over the current Canon offerings. That said, when I do use autofocus, Metabones does a nice job while using my Canon glass, even when photographing people. I'd still eventually like to try some native Sony glass with it though.

Hey Alex, would you say you like the Sony A7R2 better or the 5D Mark IV? How's the video look on the 5D?

Hey Brian,

I rarely do video, so I'm probably not the most qualified to answer that, but it's kind of a toss-up for me. I think the Canon shooting experience is vastly superior; ergonomics, menu systems, intuitiveness, button placement, etc. are all way better. But then, the files I get out of the a7R2 are so, so nice. Basically, stick the Sony sensor in a Canon body and I would be thrilled. :P

I can totally agree with that. The Sony was actually my first full frame camera. I had been shooting Canon crop sensor cameras like the 70D for years. I have to say, there's something about that vari-angle touch screen is awesome. Especially for tracking subjects during video. And I love the color science in the Canon cameras. But yeah, the Sony files are so nice. Lets face it, there will never be a perfect camera though.

Thank you for sharing my video Alex. With regard to the R2 having eye af, you’re right. I had tested that a very long time ago, but for all intents and purposes it would never work for me because of its limitations. With the new R3, it has been wonderful. After I created the video, I did notice that there is a little bit more shutter lag when adapting glass, but other than that and the tiny decrease in performance compared to native glass, it is wonderful. Again, thank you for sharing my video!

Found something cool out - Eye AF works in both Advanced AND Green modes on Metabones IV adapter (on my 24-105). It says that it should NOT work in Green mode for the a7rii (doesn't mention iii). I'm not certain on consistency yet, but, in good light, both modes pop up the eye AF box properly.

Does anyone know if the Canon 50mm f1.2 works with the Metabones 5 on the Sony A7r III ? Thanks!

Nice one for the post iv been looking at the Sony a7R III but have loads of canon glass so its hard to trade in.

So with this article and been testing at a shop. I think that this is going to be a new addition to camera equipment.

Also heard that the sigma converter is quicker is this true?