Someone who knows the uniforms better can date this more clearly, but the guitar is a 40s Kay (2nd look -- actually, it's probably a Harmony) and the tailpiece and tuners are later replacements, rather than originals (note the shape of the buttons).
Nice bass drum and Lange-made tenor jo! Mid/late '20s.
Brass group wielding a nice archtop guitar, too, aboard the Empress of Britain. '30s.
I'm guessing this was shot in the '40s. Note the excellent tamburitza instruments and then the lone Gibson mandocello in their midst! Sweet.