My rudimentary understanding is that the Fill slider controls the luminance values of pixels of low tonality, and Blacks sets the black clip point. Can someone give me a more in depth explanation of what these controls really do, and the "proper" way to integrate them into a RAW workflow?
I'd say (guesstimation inside) :
- the Fill light sets a mask on the darker parts of the image, and then lightens what's inside this mask,
- the Blacks steepens the very bottom of the tone curve, allowing to set the black level without moving the midtones. As in Photoshop, that steeper curve boosts saturation as well, and that suits me generally well in this case (after a Fill light boost).
The first operation offsets the black level to a higher value, making the darkest parts of the image ("shadows") appear weak, and decreases a bit the contrast in the "darks" - that's what the subsequent Blacks boost is made for.