This photo was with the research of our grandmother's sister and we believe it could be William David Thompson Lyon (1823-1892). It's labelled "possibly great grandfather Lyon". Assuming this is correct the photo would probably date from the 1860s and would be one of the oldest family photos. More research is needed.
From left to right: Alberta Frances Winduss (nee Johnson) (1879 - 1935), Albert Gleadow Winduss (1877 - 1963), Unknown (probably one of the Johnsons from the notes below), (probably) William Johnson (1877 - 1960), Sarah (Jane) Johnson nee Exell (1878 - 1953), (probably) William Exell Johnson (1905 - 1935), Frances Helen Johnson (nee Lyon) (1853 - 1927), the daughter of William Lyon and Sarah Lyon (nee Knight)
*Depending on the date of the photo, the younger of the Johnsons in this photo could be either:
Rudolph Jacob Johnson (1880 - 1927) aged 26 in 1906
Cyril Henry Johnson (1884 - 1954) aged 22 in 1906
Harold Leo Johnson (1891 - 1962) aged 15 in 1906
Tasman David Johnson (1894 - 1959) aged 12 in 1906