Canon EOS R50 Mirrorless Camera (White) - Manual (Page 157)

Slow Synchro
You can set the flash-sync speed for flash photography in < Av > or < P > mode.
1/250-30sec. auto ( )
The flash sync speed is set automatically within a range of 1/250 sec. to 30 sec. to suit
the scene's brightness. Slow-sync shooting is used in low-light locations (under some
shooting conditions), and shutter speed is automatically lowered.
1/250-1/60sec. auto ( )
Prevents a slow shutter speed from being set automatically in low-light conditions.
Effective for preventing subject blur and camera shake. Light from the flash provides
standard exposure for subjects, but note that backgrounds may be dark.
1/250 sec. (fixed) ( )
The shutter speed is fixed at 1/250 sec., which is more effective in preventing subject
blur and camera shake than with [
1/250-1/60sec. auto ]. However, in low light, the
subject's background will come out darker than with [ 1/250-1/60sec. auto ].
Caution
To use slow-sync shooting in < P > or < Av > mode, set to [ 1/250-30sec. auto ].
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