Prue, this is a long saga having read the threads back to 2005. Have had a read through and the arm crest seems to be a problem. The outer seems to be a "chain of office" with the shield in the middle. There seems to be an Ox-eye daisy top left, with double flowers below. Top right, figure standing, but that's all I can make out. And that was from looking at all the posted versions of the photograph.
I did come across the following, Henry Dobson, (27) bac gunner, married Lucy Griffin, (20) on 19th Jan' 1891 at Coventry. Henry's father, Jethro Dobson, waterman, Lucy's father, William Griffin, butcher, witnesses, Thomas Holtom, Abigail Fell.
Regards
Malky