[singlepic=866,379]

This rare picture was taken inside Baile na Cille Church (1950s?) and contributed by Peter N Macdonald.  The minister is Rev Angus Macfarlane and the precentor (top left) is Peter Macdonald 5 Crowlista.  Can any of the others be identified from the backs of their heads?

Edit: immediately identified, thanks to Pat.  See comments for detail.