Whites and Blacks
Raw processing sliders that set the extreme ends of the tonal range, independently of the highlight and shadow controls.
Measured in
stops
In depth
Whites and blacks establish where clipping begins, while highlights and shadows redistribute tones inside those limits. Setting the endpoints first gives the image its full contrast range, after which the interior controls can recover detail without the picture looking flat and grey.
Examples in practice
Holding a modifier key while dragging the blacks slider shows exactly which pixels are about to clip to pure black.