Dermablend Professional Compact Setting Powder (****) is essential to finish surface & extend coverage of foundations and concealers.  Because of its content of white talc, which is brighter than a skin tone, applying it may brighten the skin.  Thus, it seems to be not only useful in small amounts not to change the effect of a foundation or concealer perfectly matching the complexion and thus expensive to cover thoroughly with a thick matching layer, but rather useful in bigger amounts to brighten the effect of a small amount of a foundation or concealer to cover the discolorations with a thinner layer showing slightly trough and thus cheaper than the former, but not producing artificial, mask-like effect, and requiring more artist-like skills.