Sony A7iii focus issues (again): user error or camera fault?

Hi guys,

Having read all the threads on A7iii autofocus issues (especially the epic one from 2018 ), I’m still here to ask for advice.

I own A7iii for about a year shooting mainly with the 55mm 1.8 Zeiss lens, mostly portraits and family pictures with a toddler. From the beginning I was so disappointed with the results - too many images came out blurry or misfocused - that I even put the camera away for a while. Until recently, when I decided to do a thorough testing.

I typically take portraits with AF-C, enforcing Eye AF by a dedicated back button (AF-ON). I assume that the back button Eye AF fully overrides the shutter AF (found also several confirmations of that here on dpreview). When the subject moves, I keep the Eye AF button pressed and the camera shows that it’s tracking the eye all the time. But more than 50% of portraits come out front focused:

Here the camera showed it locked focus on the eye, but it's the hair that is in focus

This was a series of 3 identical pictures, where only the last one was focused properly

This one is focused on the eye

This was especially frustrating since this very camera was sometimes able to focus on the eyes perfectly:

So this I consider a perfect focus and this is what I compare to

All the examples above didn’t involve almost any movement. With moving people, the results were much worse.

Then I asked my husband for patience, and did extensive testing of the Eye AF and other focus modes and areas, in static and slow motion, at various apertures. The general conclusion is that something is subtly wrong with the AF, probably it tends to front focus, maybe in 50-70% of the cases. Larger DOF helps of course, but it's a shame not to be able to use the shallow one... Another conclusion is that the tracking of even a slowly moving subject is not reliable – but here I’m also not sure if that’s normal for this camera and I’m just expecting too much.

Examples:

AF-S, f/1.8, Eye AF

If I press the zoom button in playback mode, the camera shows it has focused on the right eye (right for the observer). Expected DOF for the distance is 6 cm. For me it doesn’t look like the right eye is pin sharp here… Or would you consider this result acceptable?

AF-C f1.8, Eye AF

Camera thinks it has focused on the left eye (for the observer). For me this looks front focused. What whould you say?

Here's an example of series with the subject slowly walking towards the camera from approx. 2.5 meter distance. AF-C, forced Eye AF, drive mode continuous low, 1/400 (should have excluded motion blur, right?)

This is the better one of the two equivalent series (in the other one, only the 2 first images were sharp). The camera always showed that the focus was locked on the eye.

7460  ok

7461 a bit blurry??

7462 ok

7463 ok

7464 blurry?

7465 ok

7466 front focus?

7467 not in focus

7468 ok, eyes are in focus

The more I look, the more I’m not sure – am I asking too much and maybe that’s a quite OK result of the tracking for A7III?

And the last question – do you think it makes sense to send the camera with this report to the service center, as it’s still on warranty?

I would be extremely grateful for your opinion and advice!

Olga