William Dent

A photo of William Dent and Susan (nee Crabb) and James Johnson and Mary (nee Dent) family which I think includes the daughters-in-law Clara May Ford, Emily Jane Elton, Margaret Helen Leslie and son-in-law Skelton Head and have narrowed the date to possibly being between 1868 when the Dent's youngest son Charles married Clara Ford and 1870 when Skelton Head was accidentally killed in a shearing accident.

.Standing: James JOHNSON 44 years of age and wife Mary (DENT) [33] - Skelton HEAD and wife Anne [DENT) [31], William DENT [29] wife Emily Jane (ELTON) - Isaac Dent [27] wife Margaret Helen (LESLIE)
Sitting: Charles DENT [23] - Susan and William DENT both aged 60 - Charles' wife Clara Mary (FORD)
Centre front: JOHNSON daughters Sussanah [9] Margaret [11] and Eliza [13]

N.B. Names and date are based on family resemblances, age of Johnson daughters and marriages of Dent sons and daughters which narrows date down to between 1868 when Charles Dent married Clara Mary (FORD) and 1870 when Skelton Head was killed in a shearing accident. Given the seating arrangement, with Charles and Clara taking "centre stage" alongside Susan and William, this photo may actually be commemorating their wedding on 29th October, 1868.