I've seen three of those moths in person, Polyphemus, Luna, and what I think is the Imperial moth. The yellow IO moth is another one I might have seen too.
Looking at the original picture on my screen they all seem life sized! Your suggestion of making posters is a great one because I'd certainly buy one.
How does this scanner work? All scanners I know would smash these things. :D
I left the lid open and placed a black box over the moth as I scanned it