Sony ILCA-99M2 - Manual (Page 155)

Setting of the AEL button
We recommend that you set MENU
→
(Camera Settings2)
→ [Custom Key(Shoot.)] →
[AEL Button] to [AEL hold] when performing wireless flash shooting.
Note
The off-camera flash may emit light after receiving a light signal from a flash used as the controller of
another camera. If this occurs, change the channel of your flash. For details on how to change the
channel, refer to the instruction manual for the flash.
Two flashes (a controller and an off-camera flash) are required for light signal wireless flash
shooting.
HVL-F20M can only be used as the controller.
[137] Shooting Using the flash
Using a flash with a sync terminal cord
Hint
If the screen is too dark to check the composition, set [Live View Display] to [Setting Effect OFF] to
make it easy to check the composition when shooting with a flash.
Flashes that have a sync terminal with reversed polarity can be used with this product.
Note
Set the exposure mode to manual exposure (other than ISO AUTO is recommended for ISO
sensitivity), and set the shutter speed to the slower of the following values or slower:
1/200 seconds
Open the cover of (flash sync) terminal (A), and connect the cord. 1