Now we move into the three-tone image processing, generally the way Den outlines the process. This is the beginning of the process to make the mask for highlights. After we get as far as the screenshot shown, I blurred the mask with R=60, and subtracted a mask using a histogram with control points at (50,100) and (70,0, did a feather of -2 followed by one of +2, saved the mask as HighMask.