Sony ILCA-99M2 - Manual (Page 279)

Select [1(Locked on)] to keep the focus on a specific subject when other things are crossing in
front of the subject.
[292] List of MENU items Camera Settings1
AF w/ shutter (still image)
Selects whether to focus automatically when you press the shutter button halfway down. Select
[Off] to adjust the focus and the exposure separately.
Menu item details
On:
The auto focus operates when you press the shutter button halfway down.
Off:
The auto focus does not operate even if you press the shutter button halfway down.
Useful method to micro-adjust the focus
Activating the auto focus function with a button other than the shutter button makes possible
more accurate focusing in combination with manual focusing.
SAM lenses other than SAL18135 lens do not support the DMF (Direct Manual Focus)
function (as of the day this camera was released).
[293] List of MENU items Camera Settings1
Eye-Start AF (still image)
MENU
→
(Camera Settings1)
→ [
AF w/ shutter]
→ desired setting.
1
Attach an SSM lens or SAL18135 lens to the camera, and then set the focus mode switch
on the lens to "AF." 1.
Set [ AF w/ shutter] to [Off]. 2.
MENU
→
(Camera Settings2)
→ [Custom Key(Shoot.)] → assign the [AF On] and
[Focus Magnifier] functions to the desired keys.
3.
Set [ Eye-Start AF] to [Off] to avoid auto focusing when you look through the viewfinder. 4.
Press the key to which the [AF On] function is assigned. 5.
Press the key to which the [Focus Magnifier] function is assigned, and then rotate the focus
ring for micro-adjustments of the focus. 6.
Press the shutter button fully down to shoot the image. 7.