Sony a7C Mirrorless Camera (Black) - Manual (Page 96)

Help Guide
Interchangeable Lens Digital Camera
ILCE-7M3 α7III
Focus Hold
Locks the focus while the key to which the Focus Hold function has been assigned is pressed.
Related Topic
Custom Key (still image/movie/playback)
4-732-947-11(1) Copyright 2018 Sony Corporation
MENU→ (Camera Settings2)→[ Custom Key] or [ Custom Key] →assign the [Focus Hold]
function to the key of your choice.
1
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
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