Canon PowerShot A 640 User Manual page 161

Using an Externally Mounted Flash
(Sold Separately)
High-Power Flash HF-DC1
This flash is used to supplement the camera's built-in flash when
the subject is too far away for proper illumination. Use the following
procedures to affix the camera and High-Power Flash to the
supporting bracket.
Please read the instructions accompanying the flash along with this
explanation.
I
Bracket
(Comes with the flash)
»
"
"
(I)
::s
c.
><"
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