A big difference is bit depth. BMP normally is 8bits per pixel per channel (colour). RAW is often more bits (say 10 or 12 or even more). This means you can adju

A big difference is bit depth. BMP normally is 8bits per pixel per channel (colour). RAW is often more bits (say 10 or 12 or even more). This means you can adjust lighting without introducing banding and so on.