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I didn't know about global shutter, neat. Details from the article:

What is a global shutter?

Global shutter is a method of ending an exposure where all the image data is captured simultaneously. This is distinct from most existing shutter systems (electronic and mechanical) that start and end progressively: working their way across the sensor.

There are multiple benefits to such a system, with the most obvious being the elimination of the rolling shutter distortion effect often seen on video and with slow electronic (progressive) shutters.

But another major benefit is that a global shutter can sync with flash at almost any shutter speed. With global shutter it's the duration of the flash burst that becomes the limitation, rather than the length of time it takes to close the shutter (which in turn dictates the shortest period where the whole sensor is exposed). Sony says the a9 III can sync at all shutter speeds (all the way up to 1/80,000 sec).

A global shutter also eliminates the banding that can occur with progressive shutters under flickering lights. Because the image is all captured at exactly the same moment, you don't capture different parts of a light's flicker cycle in different parts of the image. You might capture an image of an LED sign board refreshing, if you use a very high shutter speed, but that's an issue with the LEDs, not the camera, which is accurately capturing a single moment in time.