Auto mask does not change color of B & W photos

I thought I’d try colorizing a B & W photo.

Selected the photo, selected Local Adjustments, right click, select Auto Mask, “painted” a portion of the photo, selected Color in the Equalizer and moved Hue: Very, very faint color change, almost nothing.

The Brush and Control Points behave the same way.

The same process on a color photo does cause pronounced color changes.

Shouldn’t this be expected behavior? A black and white photo is desaturated and hence has a radius of 0 in the HSL color space. Rotating the hue around the centre with a radius of 0 does not change anything:


My error is in thinking in terms of Photoshop. There you select an area, select Hue and change the color.

Thanks for the color space explanation. Now the PL behavior makes sense