High-speed photography enables us to see the beauty of some of nature’s most spectacular effects, such as lightning strikes. Ningyu Liu at the Geospace Physics Laboratory at the Florida Institute of technology recorded lightning during a storm. He filmed it at 7000 frames per second and with the playback speed reduced to 700 frames per second, the result is quite beautiful.
Mano Singham
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It’s impressive because as you increase the frame rate, you (of course) cut down the exposure time. So 1/7000sec exposures with an F1.2 lens is going to need an effective film speed of around ISO 32000 even in bright daylight -- which that isn’t. On the other hand, the lightning is mighty bright and this isn’t about getting a full zone exposure range.
So the “stroke” leaves a brief bright line in the sky, but the serious “flash” happens only at grounding?
As I understand it, the downward part is just opening the conductive channels through the air. There might be plasma involved. When that hits the ground, the electricity flows from the ground upwards.