Sony A7RII Continuous AutoFocus Test Video With Sigma 50mm f/1.4 – DPReview

DPReview.com got their hands on a pre-production Sony a7RII and paired it with a Sigma 50mm f/1.4 lens and the Metabones Smart Adapter III. This Sony a7RII continuous autofocus test video shows the speed of the a7RII.

Keep in mind, this is a pre-production camera, which makes the results pretty amazing. The firmware for the a7RII isn’t even finalized yet and the video shows that the camera focuses as fast (or faster) than a DSLR—at least according to DPReview and this video test.

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This paragraph from their test notes (which we’ll quote below) says a lot:

In fact, it’s this accurate phase-detect AF that allows the a7R II to potentially focus the Sigma 50mm F1.4 lens with far more accuracy than a DSLR. You’ll note that none of the shots in this video show any sort of systemic front or back focus. No microadjustment is needed for accurate shots at F1.4, because the system is simply accurate to begin with, as phase measurements are made on-sensor and do not need any correction factors for optical artifacts like residual spherical aberration. This is potentially game-changing: focus at F1.4 without microadjustment? Yes, please.

This is game changing, though they also found a few issues. At least as of this pre-production camera the system isn’t capable of using all AF modes with third-party lenses on a converter. As a result, you’ll see that the camera often focused on the subject’s nose, not his eyes–Eye AF isn’t available as of yet with third party lenses.

Again, it’s really important to remember that DPReview was using a pre-production camera. Limitations they found in this unit may or may not be present in the final shipping units.

But even if the a7RII doesn’t launch out of the gate with the ability to capture with third party lenses in face-detect mode, it wouldn’t reduce the benefits of the system with Sony lenses, and there are numerous situations where even the pre-production focus capabilities would be more than enough for perfect shots. (You don’t need face detect focus to capture a soaring eagle or a racing Formula 1 car, for example.)

Of course, Sony isn’t in the business to make sure that Canon lenses work perfectly with Sony gear, and they didn’t claim that Canon lenses would work as well as Sony gear, only that they’d focus as fast. And based on this video, that claim is true.

Here is the full text of the DPReview test report

We adapted a Sigma 50mm F1.4 Art lens in Canon EF mount to the Sony a7R II via a Metabones Smart Adapter III. Rather than simply test the acquisition speed of AF-S, we did something far more challenging and interesting: test the AF capability of the a7R II with Canon mount glass in continuous AF mode, with subject tracking enabled to track the subject not just along the Z (depth) axis, but also across the frame, along the X and Y axes.

Given its access to image data off the image sensor at high speeds, the a7R II is capable of sticking to an initial subject quickly and accurately, ensuring that the camera knows *what* to focus on as it moves around within the scene. On-sensor phase detect AF points then ensure the camera actually focuses on what it knows to focus on, and does so *accurately* b/c the phase measurements are made by the imaging sensor itself and, therefore, do not suffer from the AF inaccuracies separate dedicated PDAF modules in DSLRs suffer from.

In fact, it’s this accurate phase-detect AF that allows the a7R II to potentially focus the Sigma 50mm F1.4 lens with far more accuracy than a DSLR. You’ll note that none of the shots in this video show any sort of systemic front or back focus. No microadjustment is needed for accurate shots at F1.4, because the system is simply accurate to begin with, as phase measurements are made on-sensor and do not need any correction factors for optical artifacts like residual spherical aberration. This is potentially game-changing: focus at F1.4 without microadjustment? Yes, please.

At the end of the video, you’ll see that, unfortunately, all the AF modes are not available with 3rd party glass on the a7R II. Therefore, it’s difficult (if not impossible) to specify *what* it is you want the camera to focus on, which makes this continuous AF mode of potentially limited value. We hope to see some of these modes enabled by Sony for 3rd party glass in future updates, if not at the very least a way of specifying to the camera what the initial subject is. In fact, it’s the fact that we had to leave the camera in ‘auto’ mode with respect to what to focus on that the nose is often focused on instead of the eye, as we were not able to specify that it is, in fact, the eye that we wish to focus on. Note that this will not be an issue for Sony lenses, where you *can* specify the subject, and even use eye AF. Still, we’d really like to see this ability with 3rd party lenses, since the camera is clearly *capable* of focusing with pinpoint accuracy on features such as the eye, even with the Canon mount lens used here.

And in case you missed it: ‘magnify’ in playback now magnifies the AF point used at capture, rather than simply magnifying the center of the frame. No more scrolling over to the point of interest in playback to check focus; you now have one-click (albeit somewhat laggy) magnification of what was focused on. This extends to all three cameras: a7R II, RX100 IV, and RX10 II.

You can find more video tests of the Sony a7RII, the RX100 IV below and the original analysis of the cameras on the original DPReview.com article.

My daily shooter is Sony a9 with a vertical grip and various Sigma lenses attached like the 14mm 1.4 Art. Find more gear recommendations in our shop. As an Amazon Associate I earn from qualifying purchases.