Thanks for contributing this comment. It's what finally made it click for me, and how logarithms might come into the picture. Especially the difference between video and still photography was helpful to me as a still photographer!
So basically, when you can't afford the space/bandwidth requirements of "raw" data for video, you need to convert the sensor readings to an actual video format right away (the equivalent of "shooting jpeg" on a still camera.)
If you do that conversion using a monotonic concave function (e.g. log) you do get an actual video, but it looks crappy because the tones are not what we would expect. However, it also retains more of the low-end distinctions of the raw data so it's more flexible in processing.
Hypothetically, I could do the same with still photography, by taking the raw data and converting it to a crappy-looking jpeg and distribute that to someone else, who would then have more freedom in processing than with a regular jpeg, but less than the raw data. I think I got it!
So basically, when you can't afford the space/bandwidth requirements of "raw" data for video, you need to convert the sensor readings to an actual video format right away (the equivalent of "shooting jpeg" on a still camera.)
If you do that conversion using a monotonic concave function (e.g. log) you do get an actual video, but it looks crappy because the tones are not what we would expect. However, it also retains more of the low-end distinctions of the raw data so it's more flexible in processing.
Hypothetically, I could do the same with still photography, by taking the raw data and converting it to a crappy-looking jpeg and distribute that to someone else, who would then have more freedom in processing than with a regular jpeg, but less than the raw data. I think I got it!