Canon Speedlite ST-E10 - Page 40

Note
Second-curtain sync works well in < > (bulb) shooting mode.
Flash units fire twice in [E-TTL II flash metering] flash mode. The first firing, which
does not indicate malfunctioning, is preflash to determine flash output.
To return to normal flash firing, select [1st-curtain sync] in step 3.
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