Lately I've been trialling out some tutorials using Curves and Selective Colour layers which have had some pretty cool results but... I'd like to know what's going on. Why they work the way they do, what it actually is they're doing. Does anyone know of any sites/tutorials/how-to guides that will explain it a little more than just giving the reader random numbers and saying "try out different settings"? Kinda like this explains colour layers and this explains blending modes.

I have this problem when I do something on Photoshop (and pretty much in every other area of my life) - I want to understand why something works and how.

Lately I've been trialling out some tutorials using Curves and Selective Colour layers which have had some pretty cool results but... I'd like to know what's going on. Why they work the way they do, what it actually is they're doing. Does anyone know of any sites/tutorials/how-to guides that will explain it a little more than just giving the reader random numbers and saying "try out different settings"? Kinda like this explains colour layers and this explains blending modes.

I have this problem when I do something on Photoshop (and pretty much in every other area of my life) - I want to understand why something works and how.