Sony A7III Manual page 13

Custom Operation1:
Photo Custom keys:
This is where you set up your custom buttons.
Movie Custom Keys:
Movie is set to follow Photo unless you change it.
Function Menu Set:
Allows you to choose what is displayed when pressing the 'Fn'
(Function)button. It is worth taking the time to set this up as it can provide
very quick access to all the settings you might want to change at the touch of
one button.
Dial Setup:
This allows you to select what way around you want the Av and Tv wheels to
work.
Av/Tv Rotate:
You can reverse the directions of these wheels if you prefer it the other way.
Playback1:
Rating Set(Cust Key):
This allows you to adjust the rating system. A good way is to only have 1 & 2
stars selected. This way you can 2 star anything you know you will definitely
use, and 1 star things you are not sure about, but might come back too. Helps
in post when looking for the good shots.
Creative Media Centre
David Turner
11 Sony A7 III Settings Guide
October 2019