D6 10 What does "automatic FP" mean?

The automatic FP mentioned by the landlord is high-speed flash synchronization, which allows the camera to flash at any high-speed shutter. At present, the brand's professional flash and high-end SLR cameras adopt high-speed flash synchronization. The principle of FP flash is that when the shutter curtain speed is too high, it will inevitably open partially and sweep the whole film range in a slit state. At this time, the flash will continuously emit multiple flash pulses until the whole curtain slit sweeps the whole picture range, so as to approximately achieve the so-called synchronization effect.

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