Sony A7S3 and A1 Back Button Focus

I spent over an hour at a Sony showroom going through the menus of the A7S3 and A1 trying to set up back button focus but was unable to do so. Sony showroom staff understood that I wanted to set up back button focus but they were also unable to figure it out.

Has anyone set back button focus with these cameras? Thanks

Hi WK,

It depends on exactly what the behaviour is that you're after, but I suspect that the setting you're looking for is called "AF w/ Shutter", which is under the AF/MF section of the menu. Regardless of whether this is on or off, you can use the AF-ON button to pre-focus. Then if "AF w/ Shutter" is set to OFF you can pull the trigger whenever you want without the camera re-focussing.

In real-world usage, I tend to leave "AF w/ Shutter" ON, function in AF-C mode and hold down the AF-ON button to initiate focus a few seconds before hitting the shutter button. In this setup the camera doesn't re-focus when the shutter is pressed (as it's already in focus). However, there may be some tricky macro situations where you might choose to shoot in AF-S, set "AF w/ Shutter" OFF and then rock back and forth to achieve perfect focus.

Hope this is helpful!

(Edit: just remembered that this was in the Video section. This was written from a photography perspective. What is the behaviour you're after in video mode? I'd be happy to try this out for you and see if I can achieve that)

(Edit 2: Just tested video out. The "AF w/ Shutter" setting isn't available in video mode, but if you want more control of the focus behaviour for video you can set the camera to AF-S mode, then use the AF-ON button to refocus, either before or during a recording)

Shane

I would think it would have to be two settings, one to enable AF with the back button and the second to disable AF on the shutter button particularly for video.  I do this for stills , I can't AF from the shutter button which is the whole point of back button AF - separating AF from making the exposure or starting the recording.

This is one of many links you can go to that have back button focus tutorials. 

www.markgaler.com:back-button-focus.webloc

Thanks everyone for your responses.

Phil,

Mark Galer touched upon what I wanted. I would like to assign a 'focus hold' function to one of the custom keys. How do I do that?

Tlhanks.

My understanding is that when you have the back button focus assigned to the AF on button and the shutter AF disengaged you focus on a subject and when you remove your finger from the button the focus is locked. Recompose and the focus distance should remain the same. Pull the shutter release and the exposure should be made without a change in focus. Then follow the same process to refocus. 

12 hours ago, Phil Rudin said:

My understanding is that when you have the back button focus assigned to the AF on button and the shutter AF disengaged you focus on a subject and when you remove your finger from the button the focus is locked. Recompose and the focus distance should remain the same. Pull the shutter release and the exposure should be made without a change in focus. Then follow the same process to refocus. 

 

Many thanks. I have visited a second Sony showroom with my GH5 in tow and the staff there have managed to identify the functionality that I am looking for is called the AF/MF toggle in Sony speak.