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Comment by DC-3 | Hacker News Reader

The first frame of that 1st video when the explosion hits is morbidly fascinating. The image looks almost as if it is pieced together from torn paper.

https://i.imgur.com/1GkJgxt.png

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Is this because shock wave compresses air and makes it refractive like water so it almost looks like there is a water droplet where the explosion originates?

That feels plausible. I think the effect of shock on the camera sensor also plays a part.

Seems like a combination of that and what seems like some algorithm performing temporal denoising on the video going haywire from the quick moving picture.

This looks like an early frame, a couple of seconds before the shock wave reaches the camera. That is why there are so many clear videos, as it takes a while for the shock wave to reach the observers - if you are 3 kilometers away, you have 10 seconds to watch the explosion, before it hits you.

Camera sensors should also not generate artifacts due to shock, unless they fail. But what is possible, that very fast moving subjects create artifacts in the image due to the limited shutter speed.

Yes. The air density changes rapidly depending on whether or not that slice of air was in the shadow of a building lengthening the path and attenuating the pressure change and it's rate of change.

This is a good article about the physics of the explosion: https://www.wired.com/story/tragic-physics-deadly-explosion-...

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