Luminosity masking are still considered something of expert or secret knowledge. Here, only a certain range of brightness is usually optimized after consuming different brightness masks were generated. Well this is only one consuming, because you can add actions and then be run with a single click such workflows yes.
Often such Luminanzauswahlen for masking curves are used with those tiny changes will be carried out in a given brightness range. Some applications that are to so see the network in which the mask must not be blurred and will not be blurred, surprises me, because to bring the luminance in a mask, you can save yourself in such a case: Simply the glare if-controller in the Layer style dialog use (in older versions of Photoshop called these "Hide when" in Photoshop CC "mixing when".
Blend-if has the advantage that you can easily store the respective brightness range as the Layer Style and apply by clicking on the Styles panel.
The areas affected by the correction after hiding your visualized in the image by your level assigns the layer effect "color overlay" mode "Normal". then this you can turn on and off as desired on demand in the Layers palette.
This way your applies, for example, Curves for color stylization or Tonwertoptimierung to individual areas of brightness - without the long detour about generating countless alpha channels, as is often carried out by conventional means.
Hide areas and visualize: Blend-if
Blend-if is only not suitable if the luminosity should be optimized manually or, such as by sharpening or smoothing. In the event there is no way around it to produce conventional Luminosity masking or convert the blend if settings in a mask. But this is another story. 😉