June 25th, 2016, 08:29
If you wish to experiment with the process used on Milton's PV-2, Here's the basic recipe (as I remember it).
1. Before you create the Alpha, switch -OFF ALL layers of the colour scheme IF they are intended to be gloss.
2. Make sure ALL other component layers are visible (shading, highlights, rivets, panels, weathering etc).
3. Go to your Channel dialogue BOX, make a Copy of Green Channel, name this Alpha 1 and invert.
4. Experiment making alterations to Brightness/Contrast until you're satisfied with the results.
Generally speaking, the lighter you go, the more you'll have to go slighly minus on the Contrast slider in order to retain just a wee tad of Alpha in the dark areas.