HIGH-SPEED FLASH SYNC
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Conventional Fill Flash
High-speed Sync
The maximum sync speed of the 800si is 1/200. However, with
the 5400HS accessory flash (sold separately) shutter speeds up
to 1/8000 can be used. High-speed sync (HSS) is particularly
useful when photographing portraits outdoors. With it, a larger
aperture can be selected to limit the depth of field and separate
your subject from the background.
Attach the 5400HS flash and set it to standard mode.
• The camera will automatically switch to HSS mode and
will appear in
the viewfinder.
• HSS cannot be used under fluorescent lights.
• The shutter will not release in HSS mode while the depth-of-field
preview button is pressed.
• When the 800si is in A mode, manual fill flash is being used, and the
scene background is very bright, HSS can be used with manual fill-flash
(p 39) to obtain a correct exposure.
• Flash bracketing is available in HSS mode.
Please refer to the 5400HS instruction manual for details.
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