In the modern digital era, that has actually changed quite a bit. Now cameras are really sensitive – the equivalent of what used to be 2500 to 4000 ISO is now really common – so instead of adding light, often you have to flag off light in areas you want dark.
So instead of many bright lights you just have duvetyne and flags everywhere, which many DoPs have complained is harder to work with.
A stop is double the amount of light. Useful for equivalence across different ways of changing exposure. So I halve my shutter speed I’ve lost a stop. But I increase my aperture from 4 to 2.8 I’ve gained that stop back. Or I double the sensitivity of my film or sensor (eg. iso 400 to 800).
So yes, in terms of data if using linear gamma exactly equivalent to bits. This is why log gamma curves are used to store for eg 16 stops of light info in 12 bit format
Imagine light represented as a floating point number of the type a * 2 ^ b
Stops describes the range of the exponent b.
With a typical cinema camera, max_b > min_b + 14
You can use tricks like gradient ND filters to increase the perceived range within of a frame or variable NDs to slowly adjust over time (like our eyes do)
pavlov|2 years ago
kuschku|2 years ago
So instead of many bright lights you just have duvetyne and flags everywhere, which many DoPs have complained is harder to work with.
franky47|2 years ago
nimbleal|2 years ago
So yes, in terms of data if using linear gamma exactly equivalent to bits. This is why log gamma curves are used to store for eg 16 stops of light info in 12 bit format
kuschku|2 years ago
Stops describes the range of the exponent b.
With a typical cinema camera, max_b > min_b + 14
You can use tricks like gradient ND filters to increase the perceived range within of a frame or variable NDs to slowly adjust over time (like our eyes do)