Paul knew the picture was from the 28th Battalion and taken in 1915 as it bore the following message on its back:
May 21st 1915 - A Comp. 28th N.W.Batt
Just a line hoping you are well. I am going to Port Arthur on monday for 2 days holiday. We leave on Wednesday the 26th for Shornecliffe, Eng. This is announced to us as official news. Will write you a letter on Monday.
Love to all,
Paul was wondering which of the men was Harry. We came to the conclusion that it was sent by Bugler 73352 Harry Griffin (front row, left end) who enlisted at Port Arthur on October 23, 1914. I noticed that this image was identical to to the one on my site (see below) down to the angle of people's heads but with the background intact. From this, I assume that the group photos were taken as above and carefully cut out as part of the layout work in printing the commemorative book I took the photos from.