Flash Off; Slow Sync - Sony DSC-HX400 Help Manual

You can set the flash mode.
1. MENU →
You can also set the flash mode by pressing the
Menu item details

Flash Off:

The flash does not operate.
Autoflash (default setting):
The flash works in dark environments or when shooting towards bright light.
Fill-flash:
The flash works every time you trigger the shutter.

Slow Sync.:

The flash works every time you trigger the shutter. Slow sync shooting allows you to shoot a
clear image of both the subject and the background by slowing the shutter speed.
Advanced Flash:
The flash automatically operates in dark locations or when there is backlighting. In dark
locations, the upper limit value of the ISO sensitivity increases in order to maximize the flash
range.
Rear Sync.:
The flash works right before the exposure is completed every time you trigger the shutter. Rear
sync shooting allows you to shoot a natural image of the trail of a moving subject such as a
moving car or a walking person.
Wireless:
When using a wireless flash, the shading effect provides a more 3D appearance to a subject
than when using an attached flash.
This mode is effective when you attach a remote control-compatible external flash (sold
separately) to the product, and shoot with a wireless flash (sold separately), placed away from
the product.
Note
The default setting depends on the shooting mode.
Available flash mode depends on the shooting mode.
The [Wireless] setting cannot be used with the camera's internal flash.
(Camera Settings) → [Flash Mode] → desired setting.
(Flash Mode) on the control button.