That's reminiscent of a (possibly apocryphal?) method I once read about to get "clean" images of normally crowded public places - take multiple photos over time, then median each pixel. Never had the opportunity to try it myself, but I thought it sounded plausible as a way to get rid of transient "noise" from an otherwise static image.

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axiolite 4 days ago | parent [-]

That's a real method:

https://digital-photography-school.com/taking-photos-in-busy...

https://petapixel.com/2019/09/18/how-to-shoot-people-free-ph...

But it only works well if the crowds move out of the way reasonably quickly. If we're taking about areas packed with people all blocking a certain area, and you need hours of shots, the change in ambient lighting over time will have negative effects on the end photo.

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aw1621107 4 days ago | parent [-]

Ah, that's the method indeed! Thanks!

	▲	aptly_yclept 4 days ago \| parent [-]
		There's an analogue method too - just do a very long exposure of a busy street. There is so little reflected light from people (relatively speaking) that it barely registers on the film/sensor, hence they are 'invisible' in the final shot. That's why old street photos are sometimes empty of people, because both lenses and film were slow, leading to long exposures.