Sony A7RIII ILCE-7RM3A Operating Instructions Manual page 190

Help Guide
Interchangeable Lens Digital Camera
ILCE-7RM3A
α7RIII
Focus Hold
Locks the focus while the key to which the Focus Hold function has been assigned is pressed.
MENU→ (Camera Settings2)→[
1
function to the key of your choice.
Focus and press the key to which the [Focus Hold] function has been assigned.
2
Press the shutter button while holding down the key.
3
Related Topic
Custom Key (still image/movie/playback)
Custom Key] or [
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Custom Key] →assign the [Focus Hold]