Digital Light & Color

As I understand it, the Weight slider determines the range of colours affected by a control point. The Brightness slider, also as I understand it, determines the mask value for the current control points.

I'm not sure, but it appears to me that the Brightness slider affects the brightness of the mask globally, i.e. not taking into account the colour-proximity of the masked pixels to the colour/saturation of the control point. If this is the case, I was thinking that perhaps weighing the brightness adjustments heavier for the colour/saturation closer to that of the control point could do an even better job in separating the colours close to the control point from other hues/saturations?

I noticed this too... ...I will usually follow the Finalized HS selections with a Mask-Brightness Curve to increase contrast to better separate the selected control point regions from the remaining HS's.

...den...

If you want changes to be more limited to the area around a control point, you need to decrease its weight. For maximum separation, turn up the brightness to 100% and select a low weight value. If necessary, you can further increase the contrast by applying a curve as Den mentions.

Brightness adjustments are already more heavily weighted for hue/saturation closer to the control point, but if you increase the weight, more pixels are brightened since more are "near" the control point.

Maybe I am missing what you are saying?

It's all good, I think I understand it better now. I thought that when the weight of a control point was fixed, and thus was its 'range of influence', the brightness slider was adjusting the brightness of the mask linearly, for all pixels influenced by the control point and its weight, but now I think it doesn't. If brightness is set to zero, all the mask pixels are black, regardless of the value of the weight, then increasing the brightness affects the pixels nonlinearly, depending on their weight, not proportionally as I thought. Thanks!

Right, the weight and brightness are independent settings. It may appear that the weight affects the brightness, only because it is changing the number of pixels the brightness applies to.