As for the baritone, who knows? The brace style could be from any English maker.Charles Keeping (c1842-) appears to have first worked as a photographer in Torquay, and moved to Exeter in the late 1860s, where he was in business until at least 1919.
As for the guy modeling, he's working out "24 Across" whose clue is "Chronosynclasticinfindibulum".
I think he's sittin' on old Fido...