My EA50 has a 'one-shot' push focus that allows me to engage auto focus while in manual mode. So what I'm wanting with my A7s is to have it in manual mode but press a button that does an auto focus while the button is down and then back to manual when released - surely I should be able to do this with the shutter release button? Can't see how.

Any ideas?

My EA50 has a 'one-shot' push focus that allows me to engage auto focus while in manual mode. So what I'm wanting with my A7s is to have it in manual mode but press a button that does an auto focus while the button is down and then back to manual when released - surely I should be able to do this with the shutter release button? Can't see how.

Any ideas?

The AF/MF (Auto focus/manual focus) button can be used to do this. It can be used while shooting video.

This is from the help guide:
Help Guide | AF/MF control (http://helpguide.sony.net/ilc/1420/v1/en/contents/TP0000226559.html)

AF/MF control

You can easily switch the focusing mode from auto to manual and vice versa while shooting without changing your holding position.
Switch the AF/MF/AEL switch lever to the AF/MF position, then press the AF/MF button.

During auto focus:
Temporarily switches the focusing mode to manual. Adjust the focus while the AF/MF button is being held down.
During manual focus:
Temporarily switches the focusing mode to auto while the AF/MF button is held down, and locks the focus.
Hint
If you select [AF/MF Ctrl Toggle] in [AF/MF Button] under [Custom Key Settings], the focusing mode remains switched even if you remove your finger from the button.

Thanks Olof - works a treat

Pete