Canon EOS Rebel XS Instruction Manual page 31

FJash Control* _w_wz;_wz_J_l_y_
The built-in flash and external Speedlite can also be set with the menu.
The menu for the external Speedlite will be applicable only to EXosedes
$peedlites whose functions ca# be set with the camera
Select [Flash control].
_, Under the [t£:] tab, select [Flash
control], then press <8>.
_ The flash control screen wilt appear
[Flash firing]
@
Normally. set this to [Enable].
If [DisabJe] isset, both the built4n
flash and external SpeedHte will
not fire. This is good when you only
want to use the AF-assist beam
[Built4n flash fuac. setting]
_, [Flash mode} cannot be selected
_, [FJash exp. comp] can be set as
explained on page 79.
_, Set [E-TTL li] as explained on the
next page
Shutter syr_c,
Normally, set this to [1st curtair_] so that the flash fires immediately
after the exposure starts
If [2r_d curtain] is set, the flash wifl fire right before the exposure
ends. When this is combined with a slow sync speed, you can create
a trail of light such as from car headlights at night With 2nd curtain
sync, two flashes will be fired Once when you press the shutter
button completely and once immediately before the exposure ends.
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