Canon EOS REBEL XS Instruction Manual page 73

E×ternai Speedlites
EOS_dedicated, EX=series SpeedJites
Basically operates Hke a built-in flash for easy operation.
When an EX-sedes Speedlite is attached to the camera, almost all the
autoflash control is done by the camera. In other words, it is like a high-
output flash attached externally in place of the built-in flash.
For detailed instructions, see the EX-sedes Speedlite's instruction
manual. This camera is a Type-A camera that can use all the features of
EX-sedes Speedlites.
Shoe-mount Speedlites Macro Lites
only [Flash exp. comp] and [E,TTL H} Can be Settable for flash function
settings (p,117) with an EX:sedes Speedlite not Controllable by the camera.
(Ear some EX:se[ies Speedlites, [$hutte[ sync,] can a!so be settab!e_)
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