Flying with Photons: Rendering Novel Views of Propagating Light

This is an improvement on a older technique: https://www.reddit.com/r/educationalgifs/comments/6wqwh1/lig...

or see https://en.wikipedia.org/wiki/Femto-photography

	▲	rtkwe 4 hours ago \| parent [-]
		Also a technique used all over the place for studying how molecules react to light. Probe it with as short of a laser pulse you can afford to buy and measure the light emitted by it some time later. My wife has been doing this basic technique for years studying things like molecules to generate fuels from sunlight. (Or was until solar energy funding as practically eliminated last year, now it's studying other things using similar techniques)

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NRHuntoon an hour ago | parent | prev | next [-]

So... why? If you care about accurate visualization of propogation of light through a complex scene, why not just do a full wave simulation? There are multiple, well studied techniques (Finite Difference Time Domain, Finite Difference Frequency Domain, Finite Element, Method of Moments...). These will give you what the light will 'actually'[1] do, not a guess based off some small sample of training data.

[1] Like with all modeling, there are of course assumptions and approximations. Different techniques have different strengths and limits. Still, these are all well vetted, studied and used by people who care about accuracy.

	▲	nlitsme an hour ago \| parent [-]
		Well, this does the actual measurement. Measurement is how deviations from theory are discovered.

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stronglikedan 2 hours ago | parent | prev | next [-]

Veritasium recently released a related video: https://www.youtube.com/watch?v=P-4pbFcERnk

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iberator 4 hours ago | parent | prev [-]

It's not real. It's rendering with some smart hacks.

	▲	zeckalpha 32 minutes ago \| parent \| next [-]
		It's measuring light through multiple samples, and then aggregating them together. Not all that different from a long exposure photograph.
	▲	nlitsme an hour ago \| parent \| prev \| next [-]
		Please define 'real'.
	▲	IAmBroom 3 hours ago \| parent \| prev [-]
		Um... "rendering" is in the title, and implies that no one is literally "flying with photons". What part did you believe was "real"?