To make this work, use the partial metering mode (or spot metering mode) over the subject where you want to lock the flash output then press the asterisk (*) button.

相机的测光方式要设置在局部测光或点测光方式，测光点对着你想要锁定曝光值的目标，按下锁定钮。

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In power system, it can excite partial parallel resonance or serial resonance, enlarge the harmonic wave, trigger relay protection system in error and disturb electric power energy metering equipment.

在电力系统，它可以刺激局部并联谐振或串联谐振，放大谐波，引发继电保护系统误差和扰乱电力能源计量设备。

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