[joshyeager]

As someone who learned photography with film in an old Nikon but hasn't kept up, how is it possible to get two extra stops from a RAW file? And why does it need to be done in post processing instead of the camera just recording the image with the sensor's full dynamic range in the first place?

[tomc1985]

It manifests as extra detail hidden in the shadow or highlights, which is only exposed when you start messing with color curves or drag shadow or exposure controls way up.

I asked a very similar question in another comment thread recently and the answer I got was that camera's awareness of the scene isn't nearly good enough when it comes to adjusting its own sensitivity curves, and that our eyes and brain are much better at postprocessing the raw data then the camera is.

[astrange]

One example is that cameras don't know what time of day it is (or rather, they could know but often choose not to care) and so auto-exposure/auto-white balance try to turn everything into noon daytime. So if you wanted your picture to look like the actual color cast and brightness you're seeing, it's up to you to remember what it looked like.

Of course, phones aren't necessarily good at this either.