What Really Happens When a Fuji X100s "Syncs" at 1/4000th of a Sec

For leaf-shutter flash geeks only: high-speed Phantom v1610 video of a Fuji X100s shutter not-quite-really syncing at 1/4000th of a sec.

Sorry, I know many of you will be bored to tears by this. But the full technical article photographer Kevin Housen developed around this video (and others, at different shutter speeds) will really peel the onion for you if you want to know about the demonstrable quirkiness of this camera and ultra-high speed sync.

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