A trail-blazer and an idealist - in a discipline she only embraced at 48 - Julia Margaret Cameron took up photography in 1863 when her daughter Julia and son-in-law Charles Norman gave her a sliding wooden box camera as a Christmas present.

Born Julia Margaret Pattle in India to prosperous parents, her family were known for being unconventional, and for being genial hosts to their network of illustrious friends.

Julia Margaret Cameron by Henry Herschel Hay Cameron, 1873 | © National Portrait Gallery, London When focussing and coming to something which, to my eye, was very beautiful, I stopped there Julia Margaret Cameron

One such, the writer William Makepeace Thackeray, coined the term ‘Pattledom’ to describe the energy and vitality of the seven sisters. This zeal also characterised Julia's approach to her art (and it was art, she insisted).

Significantly, Cameron met the astronomer and photochemistry pioneer Sir John Herschel while convalescing at the Cape of Good Hope, South Africa in 1836. Herschel is credited with coining the terms 'photography', 'positive' and 'negative' in reference to photographic images. They would become lifelong friends.

She also met her future husband, Charles Hay Cameron, there in the same year. He was a distinguished liberal reformer who in 1835 had published two essays; a critique of the tradition of duelling and On the Sublime and Beautiful, the latter of which explored questions that would become fundamental concerns of Julia's own art.

The Camerons married in 1838 and spent ten years in Calcutta, with Julia latterly becoming its foremost society hostess through organising the functions of the Governer-General of India, Lord Hardinge. They had six children of their own. Herschel also corresponded with her during this time about the latest discoveries in photography.

The Camerons retired to England in 1948, living in Tunbridge Wells then London. Charles spent extended periods at the coffee and rubber estates they owned in Ceylon. In 1859, during one such period, Julia visited Alfred, Lord Tennyson's new home at Freshwater on the Isle of Wight.

Inspired by the place, she subsequently purchased a cottage nearby, naming it Dimbola Lodge after one of the Ceylon estates, and it became the Camerons' home from 1860.

When photography became her passion, she set out to realise its potential as an art form. The hen house at Dimbola was converted to a glass house, and the coal-house to a dark room. She had no formal training and experimented with the process on a trial and error basis.

Cameron explored a variety of photographic subjects, which she herself categorised as Portraits, Madonna Groups and Fancy Subjects for Pictorial Effect in a hand-written contents page for an 1865 album for art collector Lord Overston.

She excelled in portraiture and, as an 1866 review in MacMillan's Magazine put it, her "position in literary and artistic society gives her the pick of the most beautiful and intellectual heads in the world".

Her work was sometimes criticised for its soft focus, marks and imperfections, but as she said; “When focussing and coming to something which, to my eye, was very beautiful, I stopped there instead of screwing on the lens to the more definite focus which all other photographers insist upon.

Like many artists before and since, trial, error and luck played their parts in her success.