The fellow in the center is wearing what appears to be a drummer's plaid (which is abbreviated from what piper's normally wore). The tartans worn by the guys at either end are not matched, and insignia doesn't appear to be matching for any of them (although it is unclear). The tall fellow in the back could be a drum major - if he belongs to any of these three, given the ostrich-feather bonnet. If I were to guess, I would say that this was taken of a few guys representing at least two bands at some highland games - or some official military ceremony with representatives of more than one regiment.

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