Using a supplementary flash (sold separately), High-power flash hf-dc1 – Canon PowerShot G10 User Manual
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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.
Using a Supplementary Flash (Sold
Separately)
z
The High-Power Flash will not fire under the following 
circumstances.
- When shooting in
mode
- When [Shutter Sync.] is on [2nd-curtain]
- When [Flash Mode] is on [Manual] 
z
The flash charge time will lengthen as the battery charge 
gets weaker. Always set the power/mode switch to off when 
you finish using the flash.
z
Be careful not to touch the flash window or sensor windows 
with your fingers while the flash is in use.
Tripod Sockets
Bracket
(Comes with the flash)