Canon 580EX - Speedlite II - Hot-shoe clip-on Flash Instruction Manual page 49

About Color Temperature Information Transmission
When the flash fires, the color temperature information is transmitted to
certain specific EOS digital camera . This feature optimizes the flash picture's
white balance. When the camera's color balance is set to aM> or <y >, it
wilt work automatically.
To see if this feature works with your camera, see the white balance
specification in the "Major Specifications' of your camera's instruction
manual .
Reverting to 580E Default Settings
If your EpS camera has the CLEAR > button, you can press it to revert the
camera settings (except Custom Functions) to the default.
About the AF-Assist Beam
Under law-light or law-contrast conditions, the built-in AF-assist beam will be
emitted automatically to make it eaasier to autofocus. The AF-assist beam
works with al[ EDS cameras. The AF-assist beam is compatible with 28mm
and longer lenses . The effective range is shown below.
Position Effective Range (m 1 ft)
Center 0 .6 - 10! 2 - 32 .8
Periphery 0 .6 . 5 1 2 - 16.4-
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