Well, hello and welcome to you, too............
Don't worry about alpha channels yet, you have other things to take account of, and we don't yet know how P5 will change things!!
Firstly, it is VITAL that you choose good lighting conditions, no haze, sunny but no deep black shadows, and conditions that will maintain as unchanged as possible for the duration of the picture taking.
Does your club patch pilots position face square down sun, at least, at a time you can shoot when on-one else is around?..........FAR too many of the Phoenix sites are "into sun" so the plane is a silhouette and the contrast is shot, avoid that at all costs!
Someone did a set for one of my clubs patches, but the day chosen was as flat and uninteresting as a cold pancake, it made everything else double difficult and the end result was disappointing.
Getting a decent balanced set is harder than it looks!! Good Luck.