Canon SPEEDLITE 430EX II Instruction Manual page 35

The periphery or bottom of the picture looks dark.
• When you set the flash coverage manually, the setting was a
higher number than the lens focal length, resulting in a dark
periphery.
.. Set the flash coverage that is a lower number than the lens focal
length or set it to auto zoom. (p.18)
• If only the bottom of the picture looks dark, you were too
close to the subject.
~
Keep at least 0.7 m/2.3 ft away from the subject.
The flash exposure is underexposed or overexposed.
• There was a highly reflective object (glass window, etc.) in
the picture.
~
Use FE lock. (p.15)
• The subject looks very dark or very bright.
.. Set flash exposure compensation. For a dark subject, set a
decreased flash exposure. And for a bright subject, set an
increased flash exposure. (p.14)
• You used high-speed sync.
~
With high-speed sync, the effective flash range will be shorter.
Make sure the subject is within the effective flash range displayed.
(p.16)
The picture is really blurred.
• The shooting mode was set to
<Av>,
and the scene was
dark.
.. Use a tripod or set the shooting mode to <
P
>. (p.12)
The buttons do not work.
• The Mode Dial is set to a Basic Zone mode.
.. Set the Mode Dial to a Creative Zone mode.
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