Sony A7 III A7iii AF On Button function

[Cuppa]

Hi Folks,
Is the AF On button the same as back button focussing? If not, how does it differ?
I was used to using BBF on my A6500 & would happily set it up on the A7iii utilising the AF On button if I am not going to lose another useful function by doing so.
I have a feeling that by utilising the AF On button for BBF it will simply be a case of 'cancelling' the 'half shutter release focus function'?

 

[Slug]

That's what I use it for.

 

[Cuppa]

That's what I use it for.

Ta, do you mean with half shutter release cancelled & just the AF On as supplied?

 

[Slug]

I haven't cancelled that function as I don't always BBF. I've just got used to focusing one way or the other.

 

[Deleted Member 5003]

I can only talk from the A1 and A9 perspective but assume the A7iii is the same and basically I have kept AF on my shutter half depress but I have also set AF ON to "REG Area + AF ON" basically this lets you have your shutter set for say "wide area" and have your AF ON button customised with REG Area + AF on which basically means when i depress my AF ON button i get "zone area" as per my registered area setting whilst the same shutter speed and other settings are the same as under shutter operation, for taking the shot you still have to use the shutter button it is a slight alternate to pure back button focussing. In practice if I am shooting birds in an open area and working with my shutter front button I can immediately switch to zone area by pressing AF ON if my subject is not in clear area and i need to reduce the focus area...it is really helpful

Worth looking at.......

 

[Deleted Member 5003]

Just for your further info Cuppa i also have my AF-L button set at small expanded spot with associated fixed iso and shutter speed changes for shooting static subjects........so in the field i do not have to take my eye off the EV to switch between wide area + 2000 shutter speed and main settings on depressing my shutter button, AF ON button set to REG area + AF ON giving me zone area and auto focus with all other settings as per my shutter main settings (pressing AF ON button first to focus then depressing my shutter button to shoot, much like back button focussing) and my AF L button set to registered custom settings at a lower shutter speed(around 1/750) and iso and aperture modified accordingly and again depressing the AF-L button and focusing on my subject before depressing my shutter button to take the shot.

This works very well for me ....in addition i have my modes 1,2 and 3 preset for portraits, action and landscapes so again if I need to I can quickly change to any of these more detailed alternate settings quickly and be there or there abouts(with minor tweaking) to carry on shooting.........