This is the only methor for me to key out luminance in VEGAS Pro, which is time consuming and not professional way to do so (Premiere Pro just simply drag & drop luma Key FX). You will need a 3rd party plugins from BCC just to reduce the step & layer required to mask out a luminance in your video.
Anyway, Last time I used this mask generator to replace the sky by inverting the FX it work pretty well, but It seems to leave a weird glitch. I've made a forum post about it before but no one cares?
But this time when Inverted the mask generator FX it doesnt mask out the sky at all or any highlight section.