Sony ILCA-99M2 Manual page 109

Set the mode dial to S (Shutter Priority).
1
Select the desired value by turning the front/rear dial.
2
If proper exposure cannot be obtained after setup, the aperture value on the shooting
screen blinks. If this happens, change the shutter speed.
Adjust the focus and shoot the subject.
3
The aperture is automatically adjusted to obtain proper exposure.
Hint
Use a tripod to prevent blurring when you use a slow shutter speed.
When you shoot indoor sports scenes, set the ISO sensitivity to a higher value.
Note
The SteadyShot warning indicator does not appear in shutter speed priority mode.
When [ Long Exposure NR] is set to [On] and the shutter speed is 1 second(s) or longer, noise
reduction will be done after shooting for the same amount of time that the shutter was open.
However, you cannot shoot any more while noise reduction is in progress.
The brightness of the image on the screen may differ from the actual image being shot.
[85] Shooting Selecting a shooting mode
Manual Exposure
You can shoot with the desired exposure setting by adjusting both the shutter speed and
aperture.
Set the mode dial to M (Manual Exposure).
1
Select the desired aperture value by turning the front dial.
2
Select the desired shutter speed by turning the rear dial.
You can change the setting of the front/rear dial using MENU →
(Camera